BOSTON – From the moment Kevin Garnett marched into the locker room, he dictated the terms of everything: the selflessness, the fever pitch, the way these Boston Celtics played basketball. Rajon Rondo never did love the term "Big Three," because it left someone out, someone who understood that it wouldn't be long until he was the franchise's best player. These were two willful, stubborn spirits, inspiring clashes that were epic, enduring and inevitable.

The Celtics won the NBA title in 2008, Garnett went down in 2009 with an injury, and Rondo went wild without him, responding with a rapid rise into stardom. His talent exploded, his command of the Celtics evolved and Rondo damn near averaged a triple-double in that '09 postseason.

And then they would return together in the 2010-11 season, and the dynamic between them had changed. In Garnett's absence, Rondo had become indispensable to the Celtics' success. The way coaches and teammates privately described it, Garnett could no longer dictate to Rondo.

And now the dynamic makes these Celtics still so dangerous to the Miami Heat in the Eastern Conference finals. Together, they played the biggest part in Boston's 101-91 Game 3 victory on Friday night at the Garden. Garnett had 24 points, 11 rebounds and had his way around the basket. Rondo had 21 points, 10 assists and six rebounds, and made every fourth-quarter play the Celtics needed to hold off the Heat.

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Together, Garnett and Rondo have been Boston's most consistent two stars in these playoffs.

Together, they've found a commonality of cause.

Together, they drive these Celtics now.

"There were times when they really clashed," Celtics coach Doc Rivers told Yahoo! Sports on Friday night. "But the difference now? They clash and recover. They have an amazing friendship now. But it took time. It took time, and it took trust."

Desperation delivered the day for the Celtics. Down 2-0, down over a devastating Game 2 overtime loss, this was an impassioned pursuit of victory. After Rondo's 44 points on Wednesday night, there was nothing Rivers needed to tell his point guard except this: Keep running the team. They had been so fortunate with his deft outside shooting, but Rivers understood those jumpers are fool's gold, and above everything else, the ball had to go somewhere else on Friday night.

"Throw it up!" Doc Rivers told Rondo and his teammates. Garnett is the tallest player on the floor, and sometimes basketball can be so simple this way. "Throw it up in the air," Rivers told them. "Kevin will go get it."

So they started lobbing passes over the fronting Heat defenders, and there was Garnett catching the ball and making his moves on Miami. Garnett had made his career shooting those arching jumpers, but he was determined to pound the Heat inside the paint. This made life easier for the Celtics' shooters, and Paul Pierce (23 points) and Ray Allen (10 points) benefited. Most of all, Garnett, Piece and Rondo made 18 trips to the free-throw line.

No one in New England was grumbling about the free-throw discrepancy anymore, not when Dwyane Wade did something that seemed impossible: play 41 minutes and never shoot a free throw. What's more, James had to work feverishly for his 34 points, missing four of his five free throws.

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The Celtics accomplished nothing on Friday night, except sparing themselves the humiliation of a sweep. Nothing gets serious unless Boston beats Miami in Game 4 on Sunday, unless this series goes back to Miami for a Game 5 with the teams tied, with pressure on the Heat. Between now and then, the Heat were left to answer questions of how the blend of Garnett's physical and mental warfare has impacted them. They hate talking about him, almost as much as playing against him. Garnett has made himself such an annoyance to the Heat, such an instigator. After two Heat players hit him hard, leveled him to the floor, Garnett didn't get up. He did something else: pushups. Right in the lane, right under the basket, he did eight pushups on his knuckles.

"That was his opportunity to show them that they can keep hitting him," Boston's Keyon Dooling said.

Mostly, it was his opportunity to do what he does best: Be an obnoxious agitator to these Heat. He caught a technical foul for swinging an elbow. He kept talking and talking on the floor, trying to bait every Heat player into some kind of distracting scrape.

Garnett has had a second wind to his career at 36 years old, and he's loved that it's allowed him to play longer, and play better, alongside Rondo. Whatever frustrations Garnett had with his point guard, he'll never ever forget the way that Rondo wouldn't let a dislocated elbow chase him out of the Miami series a year ago. Eventually, Rivers made Rondo leave the lineup. Never his call. He would've played one arm, and turns out, did play with one arm.

In so many ways, Garnett thrives over the daring, defiant nature of his point guard. Together, they ran roughshod on these Heat in Game 3, but the truest test comes on Sunday. "It's desperation," Garnett said. "Desperation basketball."

No one does desperate the way Garnett does, and the Celtics know that they'll forever find that balance of Garnett's delirium with Rondo's icy resolve. Garnett can be so hard on young players, but in his heart, he always believes that he's molding, preparing them to compete with him. "Kevin is such a giver," Rivers said. People don't always see that, but for those committed to winning, who care the way he does, they'll all say to a man that he's the greatest teammate that they've ever had.

"He's our best communicator," Rondo said.

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And after all these years, they share an improbable partnership for these Celtics. For so long, there was a push and pull, a fight for the soul of this franchise. Older players get perspective, and younger ones get perspective. And trust. They build trust. With the season in balance, Rondo grabbed the ball and did what he knew needed to be done with it: Lobbed it in the air, lobbed it high and trusted that it would find its way into Garnett's hands.

"He stood up to the rim and got most of them," Rondo said.

Whatever you want to say about Garnett, he's forever found a way to stand up to everything. That's why he was so hard on Rondo, why his disposition demanded that he challenge that ambitious young point guard who dared believe he belonged with the Big Three.

Clash and recover, the story of the never-ending, never-relenting fight for the soul of these Celtics.

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