The Dallas Mavericks had to give up DeSagana Diop to get Jason Kidd. Now, the 7-foot center is headed back to Dallas.

Diop agreed yesterday to a $31 million, five-year contract with the Mavericks, according to a person close to the negotiations who requested anonymity because NBA rules prevent the deal from being signed until next week.

Dallas also has agreed to a one-year, minimum-salary contract with Gerald Green, a 22-year-old former slam dunk champion who had been unemployed since March. He passed a physical yesterday and paperwork to make the deal official is being finalized. Since he wasn't on a team when last season ended, he can be signed at any time.

In other free agent news, Eddie Jones has exercised his $2 million option to return next season, when he'll be 37, and the Mavs are trying to keep their other free agents: Devean George, Antoine Wright and J.J. Barea.

Diop is a former lottery pick who was considered a bust after four lousy years in Cleveland. The Mavs signed him for the 2005-06 season and he wound up splitting the center job with Erick Dampier as Dallas reached the NBA finals. He and Dampier shared the job again the following season, when the Mavericks won a franchise-record 67 games. He was traded to the New Jersey Nets in the blockbuster trade for Kidd.

76ERS

EX-HAWK SMITH TOURS

Josh Smith wasted no time taking advantage of his restricted free-agent status, spending yesterday visiting the Philadelphia 76ers — a franchise with plenty of cap room to make a big offer.

The 22-year-old Smith toured the city and visited the Wachovia Center with Sixers officials, who would like to woo the forward away from Atlanta with an offer sheet too expensive for the Hawks to match. As he's a restricted free agent, the Hawks can match any offer made to the 6-foot-9, 235-pound Smith.

But one of Smith's agents said last night the former slam dunk champion was impressed with his tour of the city.

"They showed a very genuine interest," said Smith's agent, Wallace Prowther. "Early, early next week we'll have a much firmer grip on which direction things are going in."

HEAT

TOP PICK BEASLEY HURT

Michael Beasley's first official practice with the Miami Heat ended quickly.

Beasley was struck in the chest by an inadvertent elbow during a defensive drill about 45 minutes into Miami's first summer-league workout session yesterday, and the No. 2 overall pick in last week's NBA draft was taken to a doctor for observation.

"He took a shot to the chest," Heat coach Eric Spoelstra said. "He probably could have finished if it was the regular season or something like that, but we just wanted to be safe."

The team did not release an update on the extent of the injury to Beasley, who averaged 26.2 points and 12.4 rebounds last season for Kansas State.

OVER AND BACK

Celtics: Boston center Kendrick Perkins underwent surgery on his left shoulder yesterday. The Celtics said Perkins had arthroscopic surgery at New England Baptist Hospital, as did rookie Bill Walker, who had damage to his right knee repaired.

Nets: New Jersey signed its two first-round draft picks — Brook Lopez and Ryan Anderson — yesterday. The Nets selected Lopez with their top pick at No. 10. He led Stanford in scoring with 19 points per game last season. Anderson, selected with the 21st pick from California, led the Pac-10 in scoring with 21 points per game.