The Memphis Grizzlies have explored center Greg Oden, expressing interest in the recent past with a workout in the spring, and will potentially bring in the former No. 1 overall NBA pick to a free-agent camp in June, league sources told RealGM.

Oden, the first overall selection to the Portland Trail Blazers in 2007, played with the Miami Heat last season. He scored 67 points and grabbed 54 rebounds in 23 games.

The Grizzlies’ current level of interest in Oden remains unclear, but the franchise is believed to be having a free-agent mini-camp in the upcoming weeks -- like many organizations around the NBA. Oden is undecided in his possible participation there.

Oden's close friend and former teammate, Mike Conley, spoke late this season about the possibility of the seven-footer's comeback. Surely, Oden’s comfort level with the Grizzlies rises with Conley’s stature on the team.

In averaging 15.7 points and 9.6 rebounds, Oden led Ohio State to the NCAA championship game in 2007 and had the base of a foundational player at the NBA level. Nevertheless, knee injuries provided constant setbacks.

Oden, 27, has played two NBA seasons for Portland and one for Miami.

The Atlanta Hawks signed Paul Millsap and DeMarre Carroll on cheap two-year contracts in 2013, but the length of those deals are problematic as they are now free agents after outperforming those deals.

The Hawks offered longer contracts at the time to both players, according to sources.

Teams can go over the cap to re-sign their own players, but teams have a reduced version of that right for players coming off one and two-year deals.

Millsap’s maximum salary will be about $18.9 million, meaning that if Millsap wants his max — or thinks he can get it from another team — the Hawks will have to dip into their cap room to pay him.

The Hawks can sign Millsap to a deal starting at only $16.6 million per season if they go over the cap. If they use $19 million in cap space on Millsap, they would not have enough room left to re-sign Carroll.

Dwyane Wade opted out of the final two years of his contract that would have paid him $41.6 million and instead accepted a two-year, $31 million deal. The contract includes a player option next for $16.1 million.

Wade said last summer that he was curious to see what he could command in the summer of 2016, when the cap is expected to skyrocket from $67 million to $89 million. 

But according to associates, there is a sentiment in Wade's camp that he could opt out this summer with the hope the Miami Heat would give him a three-year deal.

The Heat would be content with Wade opting in for next season, the re-signing for significant but not huge money for another two seasons in 2016.

A sizable gap between what Wade would like over the next three seasons and what the Heat are prepared to pay him has materialized.

Marc Gasol is expected to be pursued in free agency by the San Antonio Spurs.

Gasol's free agency plans have remained a mystery and the common expectation has been he would re-sign with the Memphis Grizzlies.

"I'm a free agent, but I still have not raised anything," said Gasol of his future. "In the next few weeks, I will begin to speak with different franchises. My brother has not advised me about the different possibilities, but the decision will be complicated. My family spends time in Memphis and has even worked in the Saint Jude Hospital."

"San Antonio is an example franchise and I've always admired Tim Duncan," said Gasol. "But we'll see in the summer. "

The Spurs can create maximum contract cap space.

As Royce White attempts his NBA comeback through the July Summer League, the Chicago Bulls and New Orleans Pelicans are emerging as suitors for the former 16th overall selection in the 2012 NBA Draft, league sources told RealGM. 

White has worked out in Minneapolis this season, and recently had a workout with the Los Angeles Clippers, a source said. The Clippers, and several other teams, remain in strong contention for White's summer league decision.

DeMarre Carroll won't need to undergo surgery as he hits free agency this offseason.

Carroll was playing on a sprained knee, as well as turf toe. Carroll was unable to put any pressure on his left leg or get any elevation.

Carroll said he probably would have been out three to four weeks had the injuries occurred in the regular season.

Carroll left the door open on a return to the Hawks pending free agency talks with other clubs.

League sources told ESPN's Kevin Arnovitz that the high appraisal for Carroll is four years and $50 million.

Nick Calathes has denied a report from Spain that claimed he wants out of the NBA and has been offered to Barcelona.

"The NBA is my first priority," Calathes said.

Calathes will be a restricted free agent this summer after two seasons with the Memphis Grizzlies.

Calathes previously spent four years in Europe.

The Indiana Pacers will bring unsigned draft acquisition Stanko Barac to Indianapolis for mini-camp workouts in June, league sources told RealGM.

Barac, a 7-foot-2 center out of Croatia, turned his attention this year toward making the leap into the NBA. He signed a deal with Cedevita in the Euroleague midway through the season, gradually improving his play.

Barac went to the Miami Heat with the 39th overall pick in 2007 and was traded to the Pacers on draft night.

Indiana will use the mini-camp to decide their future with Barac and whether to sign him, or potentially include him as part of a move, sources said. Barac will travel to Indianapolis for mini-camp workouts from June 13 to June 18.

Barac, 28, had a 27-point (nine of 10 shooting) and seven-rebound performance last week against Zagrab, and is averaging 9.9 points and 5.5 rebounds per game for the season.

Barac has played professionally for Baskonia, Valencia, Efes and Cedevita.

Paul Pierce can opt out of his contract with the Washington Wizards this offseason.

Many around the league expect Pierce to opt out and finish his career with the Los Angeles Clippers. Pierce would have the opportunity to reunite with Doc Rivers while also playing in his hometown.

Pierce was pursued by the Clippers last offseason.

The Wizards thrived with Pierce as a small ball power forward.

Danny Ainge and the Boston Celtics will seek the help of Isaiah Thomas in identifying free agent targets this offseason.

“Danny said if there’s any free agent out there I’m interested in, to let him know,” Thomas said by telephone. “That has me excited. For him to ask for my input means a lot, because it means I’m definitely, right now, a part of the future, and they also value your word and what you think about the game of basketball. It means a lot, and it’s a mutual respect we have. Now, hopefully, we can get a few guys.”

Thomas did not name specific players on his wish list during an interview with the Globe, but he said a rim-protecting big man would be at the top of it.

“A defensive-minded player,” he said. “It’d be nice to get one of those in the draft. A lot of the big men out there could definitely help us out. But I know Danny is always up to something.”

Thomas also volunteered to help recruit free agents. Thomas said that when he played for the University of Washington, he helped persuade several high school prospects to join the Huskies.