There is no love lost between the Boston Celtics and former star point guard Rajon Rondo, who now happens to play for the Chicago Bulls.

Rondo was booed during pregame warmups, which clearly served only to motivate him to have a huge performance against the C's on Tuesday night in Game 2.

Rondo finished with 11 points, 14 assists and nine rebounds to lead the Bulls to a 111-97 victory and send the No. 1-seeded Celtics to an 0-2 deficit in the first-round playoff series.

However, Avery Bradley told ESPN.com after the game that Rondo's play wasn't what upset the Celtics most. No, Rondo pointed out that Bradley and his teammates had given up when things weren't going their way:

"I looked around and a few times in the game guys were putting their heads down, I think getting down on themselves," Bradley said. "But as a team, we have to stay together. The other team is looking at that. They're using that as motivation for themselves.

"I could even hear Rondo, like, 'Yeah, they gave up. They gave up.' But you never can let a team see that. You have to continue to be positive and go out there and play hard, no matter what the outcome is."

Clearly, after losing the first two games of the series at home, the Celtics are frustrated with the way they've played.

Still, Bradley is right - the way to get out of a slump isn't to hang your head. The Celtics need a boost of confidence in the worst way during these trying times.

Overshadowing any of the on-court happenings is the fact that star point guard Isaiah Thomas is dealing with the sudden death of his 22-year-old sister. He was understandably still grieving on Tuesday night as he prepares to fly back to his home state of Washington for the funeral before Friday's Game 3.

Bradley did add that it is frustrating for him and his teammates that they can't perform better for their leader during these trying times:

"You can't make any excuses," said Bradley. "Obviously, it's heavy on everyone's heart what happened to Isaiah and his family, and we were there for Isaiah. But we can't continue to say that's the reason. We just want to be there for him, continue to be there, and play hard.

"At the end of the day, we should want to play hard for each other and for him. Like, we can't sit there and keep saying, 'Oh, we're down because too much is going on.' We have to play hard, no matter what. You go through a lot throughout a season. You're going to face a lot of adversity. And the best teams overcome any type of adversity. And that's what type of team we need to be."

The Celtics face a tough road as they prepare for a must-win Game 3 in Chicago on Friday. If the Celtics can earn a road victory, they'll be able to return to Boston for Game 5. From there, anything is possible.