It's no secret that the 2007-08 Boston Celtics - a team that won the franchise's record 17th NBA championship - now has a fractured relationship.Sharpshooter Ray Allen left the team after the 2011-12 season to join the Miami Heat, Boston's biggest rival for Eastern Conference supremacy. That was seen as a betrayal by the rest of the Celtics.On Monday night, Kevin Garnett had former teammates Paul Pierce, Rajon Rondo, Kendrick Perkins and Glen "Big Baby" Davis on his Area 21 show on TNT to discuss several things about the 2007-08 title team, but one of the most enlightening segments involved their relationship with Allen.In the video below, everyone acknowledges that they weren't necessarily upset that Allen left (though they'd have preferred he not go to their biggest rival), but rather how he went about leaving Boston:

"I was initially hurt by the whole way everything went down," Pierce explains in the video. "I thought we formed a brotherhood here in Boston. Just how we carried ourselves, not only on the court, but off the court. And I just figured if it was me leaving or KG leaving, then I would have been like, 'Rondo, Perk, Baby, this is what I've been thinking about.' That's what I was hurt by - when Ray didn't just at least give us a heads-up about it."

Considering how hurt the Celtics were when the front office traded Perkins to the Oklahoma City Thunder midway through the 2010-11 season, it's not surprising that they took the Allen departure hard.

As the team plans a 10-year reunion event this summer, Perkins said it's up to Allen to reach out and make amends with the rest of the Celtics:

"Who going to break the ice? At this point and time, I don't think it's on nobody on here to break the ice," Perkins said. "I actually think it's on Ray to break the ice. If Ray wants to make amends with anybody up here or whatever the case, I think it's on him to reach out and say, 'Hey [Pierce], I handled this wrong. Man, we better than this. Hey Ticket, I handled this wrong. Hey Big Baby, I handled this wrong, or hey, Rondo, I handled this wrong, man.' Just get it past this, man. We won games together, man. We did a lot of things."

It's clear there are still some hurt feelings between the star players, even as the 10-year reunion of the title approaches.

Injuries, Kobe Bryant's Los Angeles Lakers and LeBron James signing with the Heat prevented the Celtics from winning more championships during the Big 3 era, but it was still a great time for Boston basketball.

It sounds like Pierce, Garnett and the others from that championship-winning squad are willing to welcome Allen back into the mix, but he has to make the first move. The ball is in his court now.