Defendant was indicted for criminal possession of a controlled substance in the second degree and two counts of criminal possession of a weapon in the third degree. Because the People, however, chose to rely at trial upon evidence implying that he was guilty of acting in concert or conspiring to sell drugs, and because the prosecutor improperly presented “rebuttal” testimony on purely collateral matters, I dissent. The egregiousness of this prejudicial presentation denied to defendant any *399semblance of a fair trial. I also find it offensively disingenuous of the District Attorney’s office, on appeal, to argue that these errors were not fully objected to and not, therefore, presented for review.*
This is a case where a little fish got caught up in the net with the big fish. A Drug Enforcement Task Force had been staking out a Bronx beer and soda distribution warehouse from midafternoon until just about 9:00 p.m., when they closed in and arrested the subjects of the investigation, Messrs. Zurita and Perez. The undercover officers had never seen appellant before that night and he was not arrested as, nor charged with, being part of that drug operation. Defendant just happened to be in front of that building when the police moved in and the Court of Appeals has upheld the reasonableness of the stop and search of defendant, in consideration of the “circumstances surrounding the encounter.” (People v Castro, 53 NY2d 1046, 1048, affg 80 AD2d 535.) But, “defendant was not in the immediate area in which the drug sale and arrests were taking place” (80 AD2d, at p 537 [Carro, J., dissenting]) and there was no need for the prosecutor to bring out the “buy and bust” operation in either his opening statement or his questioning of the arresting officers. The probative value of this evidence — that is, its direct relevance to defendant’s guilt of the crimes for which he was being tried — was nil. All that need have been said by the officers as “background” information was that they were at that location because of an unrelated investigation and that when they received orders from their superior officer, they detained everyone in the immediate area. “It is axiomatic that evidence of uncharged crimes may be introduced only when the testimony is relevant and necessary to the prosecution’s case (People v Molineaux, 168 NY 264; see People v Stanard, 32 NY2d 143). Moreover, in determining the admissibility of such evidence, a balance must be struck between the probative value of the testimony in connection with the crimes charged and the danger of undue prejudice *400to the defendant (People v Schwartzman, 24 NY2d 241, 247).” (People v Cook, 42 NY2d 204, 208; see, also, People v Jones, 62 AD2d 356, 357 [prejudicially “placed before the jury proof of possible other crimes, having no apparent relationship to the crime charged”] [per Fein, J.].) The prejudice here is obvious. Defendant was charged with possessing less than two ounces of cocaine and a Smith and Wesson revolver, a type commonly used by policemen. His defense was that he was charged with drug possession because the arresting officers thought he had obtained the gun by harming a police officer. Thus, his actions prior to arrest were unrelated and irrelevant to any issue he himself was raising, and the sole purpose of the prosecutor’s evidence of the surveillance operation was to provide a logical nexus which did not, in fact, exist: that appellant was a cohort of Zurita and Perez in their sale of $75,000 worth of cocaine to the undercover officers and thus had every reason to be in possession of a gun and cocaine. (Cf. People v Green, 35 NY2d 437, 442; People v Le Grand, 76 AD2d 706, 708-709 [evidence of uncharged crimes inadmissible except as explanation for some material fact].)
The People make the specious argument that the bulk of the details regarding the larger “buy and bust” was elicited through defense counsel’s cross-examination. Obviously, once faced with the prosecutor’s opening statement and the officers’ testimony, counsel was obliged to try and minimize its impact.
Likewise, defendant’s testimony as to his own actions prior to being arrested was no more than a response to evidence placing him in the middle of a drug ring. It did not open the door for the prosecutor’s “rebuttal” evidence that (1) there was no soda machine from which appellant could have bought a can, or (2) he did or did not answer questions about his prior education when later interrogated. These collateral issues pertain not a whit to whether defendant possessed drugs or a gun, and “[i]t is axiomatic that the prosecutor may not introduce extrinsic evidence to contradict a witness’ answer concerning collateral matters.” (People v Galletti, 55 AD2d 154, 157 [per Birns, J.]; see People v Milom, 75 AD2d 68, 75 [Murphy, P. J., dissenting]; People v Lizzarra, 70 AD2d 572.) Not being “inextricably *401interwoven with the crime charged” (People v Vails, 43 NY2d 364, 368), it was prejudicial error to venture into those areas. (Accord People v Schwartzman, 24 NY2d 241, 245; Richardson, Evidence [10th ed], § 491.)
Accordingly, the judgment rendered September 21,1981 in Supreme Court, New York County (Fritz W. Alexander, J.), convicting defendant of criminal possession of a controlled substance in the second degree should be reversed, on the law, and that count in the indictment dismissed.
Defendant’s counsel broke into the Assistant District Attorney’s opening statement and carefully put his objection on the record. The objection was overruled and an exception was taken. No matter what counsel later did or elicited as testimony, this objection was sufficient to preserve the issue for our review. (Cf. People v White, 53 NY2d 721, 722-723; CPL 470.05, subd 2.) Additionally, counsel moved for a mistrial both at the conclusion of the People’s case and at the conclusion of all evidence.