Adrian Wojnarowski reports from Yahoo! Sports: The Dallas Mavericks are determined to make it difficult for free agent Udonis Haslem to easily return to the Miami Heat. The Mavs have offered a contract believed to be a minimum of three years and $20 million, league sources told Yahoo! Sports. The Mavericks have offered Haslem their full mid-level exception starting at $5.85 million this season, a league source said. The Heat are trying to re-sign Haslem to play with Dwyane Wade, LeBron James and Chris Bosh, but salary cap restraints could leave them with as little as $4.3 million a year to pay him. And that’s assuming the Heat signs free agent Mike Miller starting at $4.9 million. Haslem, who made $7 million last season, has been a consistent defender and rebounder for the Heat, and president Pat Riley has been determined to keep him. He averaged 10 points and eight rebounds in seven seasons with Miami. New Jersey has shown interest in Haslem but hasn’t made a formal offer. Haslem shares the same agent as Wade and Bosh, and has expressed a strong desire to return to the Heat. Personally, I would rather the Heat spend their leftover cash after the expected signing of Mike Miller on Monday for a true center or a point guard, not a backup PF. I know Haslem has put in his time with the Heat and has been there through thick and thin but if he wasn't coming back for the minimum to retain his Bird Rights for next year, which shouldn't be surprising if he declined to do that, then I would pass. There are too many holes to fill on this roster and not much cap space left for that one more player that commands more than the veteran's minimum before the last spots get filled with journeymen or rookies. If Derek Fisher passes, who should the Heat target for that last chunk of change?