MIAMI – Alonzo Mourning once was larger than life, the Miami Heat’s biggest star. Now, even he acknowledges those days are gone.

Yet Mourning also steadfastly believes he can still play at a championship-caliber level. And now, at last, he’s back with Miami and ready to resume his past quest – delivering the Heat’s first NBA title.

The seven-time All-Star center signed a contract yesterday to rejoin Miami, the team with whom he spent eight previous seasons – a stint twice interrupted by kidney disease. He’s expected to make about $325,000 for the rest of the season, a prorated share of the $1.1 million minimum veteran contract.

“It’s definitely been a long time coming,” the 35-year-old Mourning said after a two-hour practice and 30 minutes of extra shooting drills yesterday. “It just feels good, feels good to be back home, having everything finalized. I’ve been here for the past three months training, just waiting, being patient.”

Mourning should be in uniform tomorrow when Miami visits New Jersey. He averaged 10.4 points and 7.1 rebounds in 18 games for the Nets earlier this season.

To clear a roster spot, Miami waived forward Wesley Person, who played only 27 minutes since December 4 and was displeased with his diminished role. Person may soon sign with the Denver Nuggets.

Teammates gave high marks after Mourning’s first full workout.

“He’s just going to make us a tougher team to beat,” said center Shaquille O’Neal, who also returned to practice yesterday, one week after spraining his left knee in an awkward tumble against the Chicago Bulls.

O’Neal, who missed all but the first two minutes of that Bulls game and was held out of Miami’s next three contests, said he plans to play against the Nets tomorrow.

“I went through the whole practice,” O’Neal said. “It was good.”

Miami went 2-2 in the four games where it was essentially without O’Neal, losing in overtime to the Bulls and Indiana on the road, then sweeping a weekend home-and-home with Orlando.

Miami (42-16) entered yesterday five games ahead of Detroit in the Eastern Conference, and 9 1/2 games up on Washington in the Southeast Division. Miami hasn’t been shy about tweaking its roster – last week, another Heat alum, guard Steve Smith, was acquired from Charlotte.

Smith enhances Miami’s perimeter rotation, but adding the 6-foot-10, 261-pound Mourning could create serious matchup problems for opponents – especially if he and O’Neal are on the court together.

“He’s still a very good defender and shot blocker. Those are the two main areas I look for, his defense and his rebounding,” Heat coach Stan Van Gundy said. “As far as minutes and that, or role, or who’s going to come off the bench first in the long run, I don’t have any idea.”

Mourning missed the 2002-03 season, his last with Miami, because of his kidney problems. He signed a $22.6 million, four-year deal with New Jersey, then got a kidney transplant in December 2003 and returned this season, asking to play for a contender.

New Jersey traded him to Toronto, part of the deal bringing Vince Carter to the Nets. Mourning never reported to the Raptors, who bought him out for $9 to $10 million.

“I’ve been given another opportunity,” Mourning said. “I’m going to treasure it like it’s my last.”