Disgraced NBA referee Tim Donaghy has exaggerated his cooperation in a gambling investigation in hopes of lessening his prison term and avoiding paying hefty restitution, prosecutors said in court papers filed yesterday.

He also has minimized his own role in the scheme, according to the filing in Brooklyn federal court.

Prosecutors rebuffed defense arguments that Donaghy should get a break on his sentence for voluntarily coming forward and giving prosecutors inside dirt about alleged game-fixing and other misconduct by other referees and league officials.

In the court papers, prosecutors said that by the time Donaghy decided to cooperate last year, "the government had a clear understanding of the criminal conspiracy, and who was involved." Though he deserves credit for giving investigators information on his two co-defendants, his claims of other internal NBA corruption "did not lead to evidence of prosecutable federal offenses," the papers added.

Defense attorney John Lauro declined comment yesterday.

The 41-year-old Donaghy pleaded guilty last year to felony charges of taking cash payoffs from gamblers in the 2006-07 season. He faces up to 33 months in prison at sentencing, set for July 14.

His attorney has argued that it's unfair that Donaghy's co-defendants, a professional gambler and a middleman who also pleaded guilty, are facing less time — up to 16 months and up to 18 months, respectively. Their sentencing is scheduled for July 11.

But the government papers filed yesterday argued the disparity makes sense because Donaghy was the plot's central figure.

"It was only Donaghy, by virtue of his position as an NBA referee, who had access to nonpublic and other inside information on which he based his gambling picks, and it was only Donaghy who had a duty to provide honest services to his employer, the NBA," prosecutors wrote. "Without Donaghy, the scheme simply could not have been carried out."

SPURS

HORRY WANTS TO PLAY ANOTHER SEASON

San Antonio Spurs forward Robert Horry has decided against retirement and wants to return to the NBA for a 17th season, a Houston television station reported yesterday. Horry is set to become a free agent July 1.

"I don't want to retire, especially after a year like I had last year," Horry told KRIV-TV in Houston. "I know I could have had a better year. The year started off crazy for me with family issues and then it ended crazy for me getting hurt right at the end of the season."

The defending champion Spurs lost in the Western Conference finals to the Los Angeles Lakers in five games. Horry averaged 2.5 points a game last season, 1.5 during the playoffs.

Horry, known as "Big Shot Bob" for a resume filled with clutch baskets, turns 38 in August.

BULLS

AFTER DRAFTING ROSE, CHICAGO STILL HAS ISSUES

The Chicago Bulls answered one key question when they took Derrick Rose over Michael Beasley with the first pick in the draft on Thursday.

Next question: Now what?

The Bulls insist they won't rush Rose, or rush into a trade, even though somebody figures to be the odd man out in a crowded backcourt.

"I think Kirk Hinrich can play very effectively with Derrick Rose," general manager John Paxson said. "And I think Ben Gordon can play very effectively with Derrick Rose. And I think Thabo (Sefolosha) can. And we have Larry Hughes."

But can Hinrich, Gordon, Sefolosha and Hughes all play effectively with Rose? Or does someone need to go?

"There's no set rotation right now," coach Vinnie Del Negro said. "I've met with all the players, talked to them, been around them, gotten to know them a little bit. There are no preconceived notions on anything that's happened in the past."

The Bulls entered last season expecting to contend for the Eastern Conference championship, only to unravel at 33-49.

ELSEWHERE

Nets: New Jersey extended a qualifying offer to restricted free agent center Nenad Krstic yesterday, allowing them to match any contract proposal from another team. He played in 45 games last season, averaging 6.6 points and 4.4 rebounds.