A judge warned lawyers in an insider trading case not to start a game of "gotcha" Wednesday after a prosecutor claimed a defense lawyer was celebrating in front of jurors whenever he thought he gained an advantage at the trial of a former Goldman Sachs board member.

U.S. District Judge Jed Rakoff praised the lawyers on both sides Wednesday in the trial of Rajat Gupta for their talent. But he added that he doesn't want to see them degenerate "into a game of gotcha or I can stick my tongue out more than you can."

He commented after Assistant U.S. Attorney Reed Brodsky reluctantly identified his chief adversary, Gary Naftalis, as a gloater on at least two occasions.

He said Naftalis walked away from a witness in one instance, saying loud enough for jurors to hear: "Got him!"

On another occasion, Brodsky said, Naftalis gave a thumbs-up as he walked away from a witness after he believed he had scored points.

Naftalis said he could not recall having done either and added that it was unlikely that anything he did was obvious to jurors since Rakoff didn't notice it.

The defense lawyer then questioned the fairness of Brodsky's questioning of a witness, saying the prosecutor failed to accurately recall previous testimony as he posed his questions.

"I think we're down to a very polite form of name-calling and that's not what I want to hear from either counsel," Rakoff told them. Then he suggested a cooling off period, saying: "Why don't we all go to lunch."

The exchange took place in the second week of testimony in the case against the former board member of Goldman Sachs and Procter & Gamble. Several times during the trial, the judge has told lawyers to be mindful of the effect that lengthy testimony about phone records, trading records and other evidence can have on jurors.

Jurors indicated early Wednesday that their minds might be wandering amidst the avalanche of numbers tossed their way.

Rakoff said some of the jurors had asked to know what the courtroom artists were doing. He said he could not tell them because they are not entitled to know anything beyond the evidence presented during the trial.

The government has accused Gupta of Westport, Conn., of violating securities laws by passing information in 2007 and 2008 from board meetings to Raj Rajaratnam, a one-time billionaire hedge fund founder who oversaw more than $7 billion in assets.

Rajaratnam was convicted at trial last year and is serving 11 years in prison, the longest sentence ever given in an insider trading case. The government charged Rajaratnam in 2009 along with two dozen others, who all have either pleaded guilty or been convicted at trial.