Joe Murphy/Getty Images

The Brooklyn Nets landed one of the game's premier talents when they signed guard Kyrie Irving this summer, but the six-time All-Star's off-the-court behavior has reportedly raised some concerns within the franchise.

According to ESPN's Jackie MacMullan, Irving's "mood swings ... are the unspoken concern that makes Nets officials queasy":

"When Irving lapses into these funks, he often shuts down, unwilling to communicate with the coaching staff, front office and sometimes, even his teammates. Nets team sources say one such episode occurred during Brooklyn's trip to China, leaving everyone scratching their heads as to what precipitated it. There's hope that Durant will be able to coax his friend into a better frame of mind."

Head coach Kenny Atkinson denied MacMullan's report:

Nets players expressed plenty of support for Irving to MacMullan.

"I'm sure Kyrie will have some 'days' and so will we," guard Joe Harris told MacMullan. "As long as the accountability is in place, we'll all ride with it."

Guard Spencer Dinwiddie added Irving has been a "great" teammate, per Ian Begley of SNY.tv:

Reports of unpredictable shifts in mood have followed Irving throughout the past few years of his NBA career.

Dave McMenamin of ESPN previously reported Irving went "consecutive days" without speaking to his Cleveland Cavaliers teammates during the 2017 postseason. The 2016 NBA Finals star later requested a trade during the 2017 offseason and wound up landing with the Boston Celtics.

Last season, Irving called out his less experienced Celtics teammates following a loss, saying "the young guys don't know what it takes to be a championship level team." He subsequently apologized, saying he "wanted to be the guy that led us to change" and "wanted to be the leader."

And according to MacMullan, there has already been a so-called incident in Brooklyn.

When Irving signed with the Nets, he did so alongside good friends Kevin Durant and DeAndre Jordan. Bringing in Durant—who is expected to miss the 2019-20 season due to an Achilles injury—and Jordan not only bolster the team's championship chances for the next few seasons, but it seemingly provides a support system for Irving.

Durant discussed Irving's personality with MacMullan:

"I look at Kyrie as somebody who is an artist. You have to leave him alone. You know what he'll bring to the table every night because he cares so much about the game.

"Now, it might not be how other people want him to care about it. He has his way of doing things. I respect who he is and what he does. He has all the intangibles you want in a teammate and a great player. So, how he gets to the point to be ready for 7:30 every night, I'm supporting him 100 percent."

Irving, meanwhile, spoke about the bond he shares with Durant and Jordan.

"We have the ultimate confidence in our ability to develop our relationship off the floor, to be able to protect each other as brothers and engage in family time and other things that we missed out during years we were other places," Irving told MacMullan.

Irving is off to an incredible start to his Brooklyn career, averaging 37.7 points, 6.3 assists and 5.7 rebounds per game through his first three games.