The Denver Nuggets ramped up their pursuit of Nets restricted free agent Kenyon Martin on Sunday, engaging in day-long sign-and-trade discussions with New Jersey, league sources told ESPN Insider Chad Ford on Sunday evening.

Nets GM Rod Thorn is trying to get Denver forward Nene in return for Martin, but a source in Denver told Ford on Sunday that the team would not give him up. Instead, expect the focus of the trade discussions to center on the Nuggets other 2002 lottery pick, Nikoloz Tskitishvili, who fell out of favor with head coach Jeff Bzdelik last year and played sparingly. The 7-foot-1 forward is just 20 years old and has the potential to play both the three and the four.

While sources told Ford that a sign-and-trade is Denver's preferred method to land Martin, the Nuggets have assured Martin that they will give him a max offer sheet, expected to be for six years and in excess of $80 million, if a trade cannot be completed by July 14 -- the first day free agents can officially sign. Extending an offer sheet, though, would be a "last resort" for the Nuggets, as once Martin signs an offer sheet, the sign-and-trade option disappears.

Martin, who received a similar offer from the Atlanta Hawks on Thursday night, told the Nuggets that he would accept their offer over Atlanta's if a trade does not occur, a Denver source told Ford.

ESPN.com's Marc Stein reported Saturday that the Nuggets had decided to extend an offer to Martin on Sunday morning, in the hope that it would spark a new round of serious sign-and-trade talks with the Nets.

Martin has maintained throughout the process that his first choice is to re-sign with the Nets. New Jersey, however, is balking at the money Martin is commanding and is actively in discussions with the Nuggets.

The Nuggets apparently prefer the sign-and-trade option because they fear New Jersey would match a offer sheet to Martin, and would take the full 15-day period to official match, which would tie up Denver's available cap space and would freeze them out of making other moves in the free agent market.