OPINION OF THE COURT
LEWIS, Circuit Judge.Altigraci Rosario challenges her conviction on two counts of passing United States Treasury checks in violation of 18 U.S.C. § 510(a). Of primary importance on appeal is Rosario’s challenge to the sufficiency of the evidence with regard to Count 1 of the indictment. We must decide whether a conviction for passing a treasury check can be sustained based solely on evidence establishing that the defendant possessed the check and that it was “probable” that the defendant had signed the cheek. We conclude that it can and will affirm.
I.
Altigraci Rosario operated a tax preparation service in Hightstown, New Jersey. Jose Rios, Rosario’s nephew by marriage, was employed by Rosario and assisted with her tax preparation service. In February 1993, the U.S. Treasury Department mailed a Treasury check to Angel and Ana Andrade in the amount of $2,996.00. Soon thereafter, the Andrades filed a complaint with the Treasury Department alleging that they had not received the check.
On January 11, 1994, the New Jersey National/ Corestates Bank notified the U.S. Secret Service that Jose Rios had deposited the Andrade check into his account at the bank. That same day, the Secret Service interviewed Rios. During the interview, Rios stated that Rosario had given him the signed cheek and asked him to cash it. Rios apparently received a $20 fee for executing the transaction.
In September 1993, the U.S. Treasury Department mailed a tax refund check to Ivan Vitiello in the amount of $1,943.03. Subsequently, Vitiello filed a complaint with the Treasury Department alleging that he had not received the check. In his complaint, Vitiello identified Altigraci Rosario as his tax preparer. Vitiello stated that he had authorized Rosario to have the check delivered to her post office box, but he had not authorized her to cash the check.
On May 4, 1994, a U.S. Postal Inspector confirmed that Vitiello’s cheek had been delivered to a post office box registered to Altigraci Rosario and Jose Rios. That same day, the Vitiello check was cashed at Reed’s Garage in Cranbury, New Jersey. Employees of Reed’s Garage informed the government that Rosario and Rios had cashed the Vitiello check. Sometime later, the government identified Rosario’s fingerprint on the cheek.
On November 18, 1994, the government filed a two-count misdemeanor complaint against Rosario, charging her with negotiating two checks bearing forged endorsements in violation of 18 U.S.C. § 510(a) and § 510(e). Count 1 of the indictment related to the Andrade cheek and Count 2 related to the Vitiello check. After a one-day jury trial, Rosario was convicted on both counts.1
At trial, Angel and Ana Andrade testified that they had never met Rosario, used her service or authorized her or anyone else to endorse their check. Rios, the prosecution’s chief witness, testified that Rosario had given him the Andrade check, which had been endorsed, along with a form of identification of the payee. Rosario asked Rios to cash the *162check, informing him that the payee did not have a bank account and therefore could not cash the check. (Apparently, Rios had a substantial amount of cash in a safe in the office due to a $20,000 personal injury settlement.)
Rios further testified that he had not met the persons whom Rosario told him had given her the check. Indeed, Rios stated that he '‘didn’t even see the people.” App. at 47A. According to Rios, he took the Andrade check from Rosario, photocopied the identification and gave Rosario the cash, less a $20 fee. Rios stated that he did not actually see Rosario hand the cash over to any person who might be associated with the check, but that he did see her “talking to someone.” App. at 49A.
Finally, Rios testified that after the bank informed him that the Andrade check had been reported stolen, he looked for the photocopy that he had made of the identification but could not find it. When he informed Rosario about the cheek, Rios acknowledged that she seemed “genuinely surprised” that the check had been reported stolen. App. at 54A.
The government supplemented the testimony of Rios with the testimony of a handwriting expert, Secret Service document examiner Jeffrey Taylor. After comparing the signature for Ana Andrade that appeared on the check with a known sample of Rosario’s handwriting, Taylor testified that Rosario “probably” had forged the check herself— that is, it was “more likely than not” that she had done so. Essentially, the testimony of Rios, Taylor and the Andrades constituted the entirety of the government’s case on Count 1 of the indictment.
After the jury rendered its verdict, Rosario filed a Rule 29 motion for judgment of acquittal on Count 1 with the magistrate judge, arguing, inter alia, that the evidence was insufficient to sustain a conviction.2 The magistrate judge denied Rosario’s post-trial motions. See United States v. Rosario, Crim. No. 94-5050K-01 (D.N.J. May 9, 1995).3 On June 2, 1995, the magistrate judge sentenced Rosario to eight months in prison on both counts to be served concurrently.4 At the time of sentencing, Rosario was already serving a one-year sentence for an unrelated bribery conviction.
Rosario then appealed the magistrate judge’s decision to the district court pursuant to 18 U.S.C. § 3402.5 The district court affirmed Rosario’s conviction and sentence in all respects. See United States v. Rosario, Crim. No. 96-277(D.N.J. April 3, 1996). On this appeal, Rosario’s primary challenge to her conviction is that the evidence offered at trial was insufficient to support the jury’s conviction on Count 1.6
The district court had jurisdiction over the criminal proceedings pursuant to 18 U.S.C. § 3231. We have jurisdiction over the appeal pursuant to 28 U.S.C. § 1291.
II.
Our review of a sufficiency of the evidence challenge is guided by strict princi*163pies of deference to a jury’s verdict. United States v. Anderskow, 88 F.3d 245, 251 (3d Cir.), cert. denied, — U.S. -, 117 S.Ct. 613, 136 L.Ed.2d 537 (1996). We must view the evidence in the light most favorable to the government and must sustain a jury’s verdict if “a reasonable jury believing the government’s evidence could find beyond a reasonable doubt that the government proved all the elements of the offenses.” United States v. Salmon, 944 F.2d 1106, 1113 (3d Cir.1991). Accordingly, “[a] claim of insufficiency of the evidence places a very heavy burden on the appellant.” United States v. Coyle, 63 F.3d 1239, 1243 (3d Cir. 1995).
Rosario was convicted of check forgery under 18 U.S.C. § 510(a)(2), which provides:
(a) Whoever, with intent to defraud—
(2)passes, utters, or publishes, or attempts to pass, utter, or publish, any Treasury check or bond or security of the United States bearing a falsely made or forged endorsement or signature; shall be fined under this title or imprisoned not more than ten years, or both.
18 U.S.C. § 510(a)(2).
At trial, the magistrate instructed the jury that, under the statute, the government was required to prove the following elements beyond a reasonable doubt:
(1) that the defendant passed or attempted to pass a U.S. Treasury cheek,
(2) that the check bore a forged or falsely made endorsement,
(3) that the defendant passed the check with intent to defraud, and
(4) that the defendant acted knowingly and willfully.
Rosario, Crim. No. 94-5050K-01, slip op. at 7.
Rosario contends that the government failed to meet its burden on elements (2), (3) & (4). Specifically, she argues that Rios’s testimony establishing that she possessed the check was insufficient to corroborate the testimony of the handwriting expert that she probably forged the check.
As noted earlier, Taylor testified that it was “probable” that Rosario had forged the check. “Probable” is a term of art used by Secret Service document examiners. The “probable” category falls exactly in the middle of the six-point spectrum between “positive identification” and “positive elimination.” Thus, handwriting experts will use the term “probable” to describe
times when the evidence falls considerably short of the “virtually certain” category and yet still points rather strongly toward the suspect, i.e., there are several significant similarities present between the questioned and known writings, but there are also a number of irreconcilable differences and the examiner suspects that they are due to some factor but cannot safely attribute the lack of agreement to the effect of that factor.
Thomas V. Alexander, Definition of Handwriting Opinions, App. at 37A.
The government concedes that Taylor’s testimony alone would be insufficient to sustain a conviction under § 510(a). The government argues, however, that Taylor’s testimony that Rosario probably forged the check, coupled with Rios’s testimony that Rosario had given him the check, would allow the jury to make the inference that Rosario had forged the check. Moreover, according to the government, once the jury concluded that Rosario had forged the check, it could logically conclude that she had done so knowingly and willfully and with intent to defraud. We agree. By establishing that Rosario possessed the cheek, and thus had the opportunity to forge it, the government provided validation for Taylor’s testimony that Rosario had probably forged the check.7
*164In reaching this conclusion, we are persuaded by the reasoning put forth in United States v. Richardson, 755 F.2d 685 (8th Cir. 1985) (per curiam) and United States v. Rivamonte, 666 F.2d 515 (11th Cir.1982) (per curiam). In both Richardson and Rivamonte, as here, the handwriting expert’s testimony established only that it was “probable” that the defendant had forged the check.
In Richardson, the court upheld a check forgery conviction challenged on insufficiency grounds. The handwriting expert testified that Richardson had “probably” signed the check. This testimony was supplemented by evidence that Richardson had access to a key to the victim’s home, that she had made a deposit in the exact same amount as the stolen check, and that her fingerprints were on the stolen check. In upholding the conviction, the court concluded that this was “ample evidence to support the verdict.” Richardson, 755 F.2d at 686.
Similarly, in Rivamonte, the court upheld a check forgery conviction based on the following evidence: a handwriting expert’s testimony that the defendant had “probably” signed the check; the defendant’s fingerprints were on the check; the defendant’s account number was written on the back of the check; and the payees’ names were written on the defendant’s pre-encoded deposit slip. Rivamonte, 666 F.2d at 516-17. The court held that “a jury reasonably could conclude that this evidence is inconsistent with every reasonable hypothesis of appellant’s innocence.” Id. at 517.
Although in Richardson and Rivamonte the government offered slightly more circumstantial evidence than was offered at Rosario’s trial, we are nevertheless convinced that the evidence establishing that the respective defendants had possessed the check was of primary significance in those cases. Our conclusion is bolstered by the Eleventh Circuit’s post-Rivamonte decision in United States v. Henderson, 693 F.2d 1028 (11th Cir.1982). In Henderson, the court reversed a check forgery conviction based solely on ambiguous handwriting testimony and evidence showing that the defendant’s wife had cashed the stolen check. The government offered no evidence that Henderson had ever possessed the check. Distinguishing Rivamonte, the court noted:
Although both Rivamonte and the present appeal had handwriting experts testify that the respective defendants “probably” endorsed the checks, the additional evidence in Rivamonte constituted sufficient evidence to sustain a conviction. The fingerprints and the defendant’s account number support the conclusion drawn by the handwriting expert in Rivamonte.
Henderson, 693 F.2d at 1032.
Here, although Rosario’s fingerprints were not found on the check, Rios’s testimony established that Rosario was in possession of the check. Thus, Rios’s testimony that Rosario possessed the check provided the same corroboration for the handwriting expert’s testimony that the fingerprint evidence in Rivamonte and Richardson did. See also Chatman v. U.S., 557 F.2d 147, 148 (8th Cir.1977) (per curiam) (upholding check forgery conviction because accessibility of payee’s mailbox to defendant provided corroboration for less than conclusive expert handwriting testimony).
In our view, because the evidence established that Rosario did, in fact, possess the check, the jury could have used that fact to corroborate the handwriting expert’s testimony that she had probably forged the signature on the check. While neither of these factors independently would be sufficient to support a conviction, taken together they are sufficient to support the jury’s guilty verdict.8
*165Finally, we acknowledge that this is a close case. Indeed, were we sitting as triers of fact, we very well may have come to a different conclusion than the jury did here. Nevertheless, we cannot say that there was insufficient evidence to support the jury’s verdict. Accordingly, we affirm Rosario’s conviction.
. Because Rosario does not challenge the sufficiency of the evidence with regard to Count 2, relating to the Vitiello check, we will not discuss the proof offered at trial with regard to that count.
. Rosario also moved for a new trial on both counts based upon the magistrate judge's allegedly erroneous ruling on her motion in limine.
. The magistrate judge had jurisdiction to serve as trial judge over Rosario’s trial pursuant to 18 U.S.C. § 3401, which allows a magistrate judge to try and sentence persons accused and convicted of misdemeanor offenses.
. Rosario was also ordered to pay restitution in the amounts of $2,996.00 and $1,934.00 to the victims and to pay aggregated special assessments of $50.00.
. That statute provides:
In all cases of conviction by a United States magistrate an appeal of right shall lie from the judgment of the magistrate to a judge of the district court of the district in which the offense was committed.
18 U.S.C. § 3402.
. Rosario also raises again the argument that the magistrate judge erred by denying her motion in limine to exclude the admission of her prior bribery conviction. We decline to address the merits of the magistrate’s in limine ruling because, by not testifying at trial, Rosario has failed to preserve this issue for appeal. See Luce v. United States, 469 U.S. 38, 105 S.Ct. 460, 83 L.Ed.2d 443 (1984) (holding that in order to raise and preserve for review the claim of improper impeachment with a prior conviction, a defendant must testify); United States v. Moskovits, 86 F.3d 1303, 1305-06 (3d Cir.1996) (same), cert. denied, - U.S. -, 117 S.Ct. 968, 136 L.Ed.2d 853 (1997).
. Once the jury was provided with enough information to conclude that Rosario had forged the check, it certainly could have inferred that she acted knowingly and willfully and with the intent to defraud. Of course, the requisite state of mind elements only follow if the jury believed that Rosario did, in fact, forge the check. See, e.g., United States v. Hall, 632 F.2d 500, 503 (5th Cir. 1980) (holding that once forgery was established, inferences of knowledge and unlawful intention followed). Given the Andrades' testimony that they did not know Rosario nor authorize her to endorse the check, the jury could have *164assumed that Rosario forged the endorsement of the check with the requisite intent to defraud.
. We are not persuaded by Rosario’s attempt to characterize Rios’s testimony as "exculpatory” for her. Using Rios’s testimony, Rosario implies that she merely unknowingly passed the forged check to Rios and then passed along the cash to the person or persons who brought in the check. Rosario finds further support for her theory from Rios's testimony that she was “genuinely surprised” when he reported that the check was stolen.
As the district court pointed out, however, the jury was not required to believe that Rosario made any of the arguably exculpatory out-of-court statements to Rios. Rosario, Crim. No. 96-277, slip op. at 6. And, in any event, the state*165ments she relies on are not inconsistent with guilt. Simply stated, the jury had no reason to believe that Rosario was being truthful with Rios. Indeed, the jury could have just as well believed that Rosario’s statements to Rios served to deceive him into believing that she had unwittingly passed the forged check. After all, it certainly served Rosario's interests for Rios to believe the check transaction was legitimate because Rios may have been less willing to cash the check had he known it was stolen.