Appeal by the defendant from a judgment of the Supreme Court, Kings County (Grajales, J.), rendered July 5, 1989, convicting him of criminal sale of a controlled substance in the third degree (two counts), upon a jury verdict, and imposing sentence.
Ordered that the judgment is affirmed, and the matter is remitted to the Supreme Court, Kings County, for further proceedings pursuant to CPL 460.50 (5).
We find unpersuasive the defendant’s contention that the prosecution’s evidence was not of adequate quantity or quality to sustain his conviction. Viewing the evidence in the light most favorable to the prosecution (see, People v Contes, 60 NY2d 620), we find that it was legally sufficient to establish the defendant’s guilt beyond a reasonable doubt. Moreover, resolution of issues of credibility, as well as the weight to be accorded to the evidence presented, are primarily questions to be determined by the jury, which saw and heard the witnesses (see, People v Gaimari, 176 NY 84, 94). Its determination is entitled to great deference on appeal and should not be disturbed unless clearly unsupported by the record (see, People v Garafolo, 44 AD2d 86, 88). Upon the exercise of our factual review power, we are satisfied that the verdict was not against the weight of the evidence (see, CPL 470.15 [5]).
It is obvious from the verdict that the jury, which had the opportunity to view the witnesses, hear their testimony and observe their demeanor, found the People’s witnesses credible and the defendant and his alibi witnesses, i.e., his mother, his sister and his girlfriend, not credible. Our dissenting colleague concludes that the weight of the evidence in this case supports a reversal, relying upon the considerations that this is a single eyewitness case, that the eyewitness described the defendant’s jacket as maroon when she first saw him and as black, white and red when she subsequently observed him, that no drugs or prerecorded money were found on the defendant’s person at the time of his arrest, and upon a finding that "the nearly uniform time sequences” testified to by the police witnesses *679are "somewhat doubtful”. None of these factors justifies disturbing the jury verdict. Criminal prosecutions based upon the testimony of a single eyewitness are hardly rare, as those who engage in criminal conduct generally do not do so before an audience. Of far greater significance is the consideration that the single eyewitness in this case was a trained and experienced undercover police officer who spent some 3 to 3Vi minutes in the close company of the defendant and who therefore had an excellent opportunity to view him (see, People v Wharton, 74 NY2d 921; People v Morales, 37 NY2d 262; see generally, People v Petralia, 62 NY2d 47, cert denied 469 US 852). The failure of the undercover officer to mention the defendant’s West Indian accent and the large gap in his front teeth in the description she relayed to the backup team is of no moment given that neither of these items of information would have assisted the backup officers in spotting the defendant on the street. The identification testimony of the undercover officer at trial was consistent and unwavering, and the jury was certainly entitled to credit it. That the undercover officer described the defendant’s jacket as maroon when she first observed him and then as black, white and red when she next saw him some time later does not warrant a departure from the jury’s determination of guilt. The jurors reasonably could have concluded that the officer either was initially mistaken in her description or that the defendant had procured a different jacket during the 15-to-20 minute interval between his sale of drugs and his arrest.
Likewise, the fact that no drugs or prerecorded money were recovered from the defendant fails to persuade us that the verdict rendered by the jury is erroneous. Indeed, it is observed in the dissent that the purchase of cocaine by the undercover officer exhausted the defendant’s supply of the drug. Hence, the absence of drugs at the time of his arrest is hardly shocking. Moreover, given the length of time between the defendant’s commission of the crime and his arrest, the lack of prerecorded money on his person did not mandate a verdict of acquittal.
Furthermore, the defendant’s alibi evidence is far from convincing. While the defendant’s mother, sister and girlfriend maintained that he did not leave his residence until 5:30 p.m., the backup police officers testified that the defendant had been placed under arrest no later than 4:30 p.m. The testimony of the backup officers as to the time frame was entirely consistent with the undercover officer’s testimony and directly contradicted the defendant’s alibi witnesses. Unlike *680our dissenting colleague, we do not find the police testimony in this regard to be "somewhat doubtful” because of its uniformity, as police officers are obligated, as a matter of training and duty, to note relevant time periods. Rather, it is the alibi testimony presented by the defendant which is rendered doubtful by its uniformity. Indeed, each of the defendant’s three alibi witnesses stated that she fortuitously looked at the kitchen clock at the moment the defendant left his residence; hence, each was sure that he left at 5:30 p.m. We find no difficulty in the jury’s apparent rejection of this seemingly tailored testimony. Similarly, we do not share the dissent’s skepticism regarding the ability of the backup officers to complete a thorough search of the crime scene within the period of an hour before transporting the defendant to the station house.
In sum, all of the issues raised by the dissent were placed before the jury at the defendant’s trial, and the jurors resolved each issue in favor of the prosecution. Our dissenting colleague, on the other hand, has resolved each issue in favor of the defendant. As the Court of Appeals noted in People v Gaimari (176 NY 84, 94, supra): "[the jurors] could look into the faces of the various witnesses as they gave their versions of the transaction and decide, so far as human judgment can tell, not only who intended to speak the truth, but who in fact spoke the truth. Representing the average judgment of mankind, they could separate the true from the false with a degree of accuracy which, according to the theory of our law founded on the experience of many generations, cannot be attained by reviewing judges. The memory, motive, mental capacity, accuracy of observation and statement, truthfulness and other tests of the reliability of witnesses can be passed upon with greater safety by those who see and hear than by those who simply read the printed narrative.” Inasmuch as the jury in this case has rendered a verdict which is entitled to great deference and which we do not find to be against the weight of the evidence (see generally, People v Bleakley, 69 NY2d 490), we decline to disturb that verdict.
Similarly unavailing is the defendant’s contention that the evidence adduced by the prosecution failed to sufficiently establish the chain of custody for the narcotics which were admitted into evidence. The trial testimony demonstrated that the narcotics were placed in an envelope by the undercover officer who purchased them from the defendant, and that the envelope was then sealed, marked and signed by that officer and by her supervisor, who placed it in a safe. Moreover, the *681police laboratory chemist testified that he received this envelope in an intact and sealed condition, thus providing "reasonable assurances of the identity of the narcotics and of their unchanged condition” (People v Newman, 129 AD2d 742; see, People v Wilson, 150 AD2d 628). Moreover, we note that to the extent the defendant claims the existence of a gap in custody subsequent to the laboratory analysis, "there was no possibility that [such a] gap would have permitted any prejudicial alteration of the contents of the drugs initially seized” (People v Julian, 41 NY2d 340, 344).
The defendant’s claim regarding the court’s denial of a Wade hearing in this case, has not been properly preserved for our review. However, if we were to consider it, we would find it lacking in merit (see, e.g., People v Davis, 141 AD2d 831).
We have considered the defendant’s remaining contentions and find them to be without merit. Thompson, J. P., Sullivan, and Harwood, JJ., concur.