BOSTON -- He thought he had a bum hamstring. On Saturday night, Rajon Rondo was hanging out at his friend Keyon Dooling's house watching TV, playing with the kids and, as Dooling said, "talking about life."
"He mentioned in passing his leg was hurting," Dooling said. "No big deal."
Rondo never suspected a torn ACL, which he learned Sunday would sideline him for the remainder of the season. According to Boston Celtics officials, the All-Star guard suffered the injury sometime late in the fourth quarter of Friday's loss to Atlanta, but stayed in the game and played through two overtimes in a 123-111 loss. Rondo posted a triple-double (16 points, 10 rebounds, 11 assists) in that outing, which proved to be his last of the season.
Coach Doc Rivers said his point guard was "shocked" by the news.
"He thought it was his hamstring," Rivers reported. "He never said anything about his knee. At our shootaround [on Sunday morning], he had the [ice] pack on the back of his hamstring.
"Doc [Brian] McKeon took a look and started moving it around and said to me, 'I'm telling you, that's an ACL. I'm pretty sure.'"
McKeon immediately ruled Rondo out of the Garden tilt with the Miami Heat, then sent him to New England Baptist Hospital for an MRI.
By the early moments of the third quarter, various media outlets were reporting the Celtics feared he had suffered a torn ACL.
That's when I went looking for some answers.
As I walked into the back hallway where the Celtics' locker room is located, I found Rondo himself, who was just returning to the Garden from the hospital. He was dressed in shorts and a pair of slides and moving easily, seemingly without pain.
"Hey," I told him, "people are reporting you have a torn ACL."
"Who said that?" Rondo responded. "A torn ACL? I don't even have the results yet. I'm going to see the doc right now."
As he ambled toward the locker room, he asked, "Could I be walking around like this with a torn ACL?"
"Yes," I answered. "Guys have played with torn ACLs before."
"I don't feel that bad," Rondo said. "I don't feel like I have something that serious, but I've never had one before. All I know is my leg felt funny."
He stopped in front of the locker room. I asked him how hard it was to sit out of the Miami game, which included the celebrated return of former teammate Ray Allen.
"Hell, I hate missing it," he said. "I wanted this one really bad."
Rondo disappeared into the locker room at 2:38 p.m. Three minutes later, Celtics public relations director Jeff Twiss emerged with the official diagnosis: a torn ACL, done for the season, surgery imminent.
His teammates played on, oblivious that their long-term fortunes had just suffered a serious blow. The Heat also were unaware of Rondo's plight -- until 2:50 p.m., when Dwyane Wade left the court and entered the visiting locker room, presumably to use the facilities.
"What's going on?" he asked me as he walked by.
"Rondo has a torn ACL," I answered.
"No, please. Don't tell me that," Wade said with a grimace. "Oh, that's awful. Now listen, we have a bad history, but I never wish that on anyone."
Wade passed on the news to his bench. When James Jones also retreated to the locker room in the third quarter, he offered, "Tough break for Boston. Sorry about Rondo."
The grim news of Rondo's injury passed like a wave through the stands of the capacity crowd, which, in spite of Boston's spirited play, remained subdued. Included among those fans were New England Patriots players Patrick Chung and Donte Stallworth, who stood in the hallway commiserating with each other.
"Is he still back there?" Chung asked. "Tell him we wish him the best. It's an athlete's worst nightmare."
As the game went into a first, then a second overtime, Rondo pulled on some jeans and a sweatshirt and popped out to the edge of the court to watch the remainder of the game. He was flanked by multiple security guards and his friend, Dooling.
"He's taking it OK," Dooling said. "I think he's still in shock about the whole thing."
Celtics owner Wyc Grousbeck had sat with Rondo in the locker room during the third quarter and reported he was "down but not out."
"He can't believe it's torn," Grousbeck said. "He told me, 'I'm done. Done for the year.' It probably hasn't hit him yet.
"But just after he said that, he was saying to me, 'Look at that play.' He was totally focused on the game.
"Rondo and KG are the heart of our team. Players like [Avery] Bradley and [Jared] Sullinger feed off them. It's a big loss for us."
Doc Rivers suffered a torn ACL during his NBA career. He described Rondo as "emotional" when discussing the diagnosis with him.
"I told him I remembered the next day after my [ACL tear] I felt pretty good," Rivers said. "I thought the doctors were wrong."
Even before Rondo's devastating injury, there has been a plethora of discussion about what to do to shake the Celtics out of their malaise. The suggestions have including "blowing up" the roster, with Rondo as the primary trade chip.
"I don't get that," Rivers said, shaking his head.
The coach said he wasn't sure if Boston would immediately add another player. His second unit was successful in working without a point guard during the week.
"We can still get wins," Rivers insisted. "I still like my team."
His team won a big one Sunday. It thwarted the Heat with an inspired effort that extended Miami's regular-season losing streak in Boston to 10 games, dating back to 2007.
(The key words here, obviously, are "regular season." Clearly the Heat have found ways to win when it matters most -- in the playoffs.).
Miami was gracious regarding Rondo's fate.
"It's terrible," LeBron James offered. "As much as a competitor and as much as I've been a rival with Boston over the years, I never want to see anyone go down."
It was purely unintentional, yet Rondo's injury completely upstaged the return of Ray Allen to the Garden for the first time since he chose to take his talents to South Beach.
The video tribute to Allen and the smattering of boos and round of applause were all forgotten once the Garden faithful became aware that Rondo was gone, and he wasn't coming back anytime soon.
At 4:45 p.m., as the Garden emptied out and Rondo retreated home with his family, Celtics president of basketball operations Danny Ainge was asked to make sense of an afternoon with so much promise that went so horribly awry.
He expressed confidence in his personnel, said he would evaluate what moves need to be made in the coming days, then conceded the team "will be different."
"We've had success playing for short periods of time without Rajon," Ainge said, "but we've never had to play without him for long periods of time.
"It will be an interesting test for us. Not a test we wanted. And, frankly, I'm worried about that test."
Rondo was telling friends and teammates he would be back in record time -- six months, he figured.
He said that as he walked under his own power, with limited pain and the stride of a defiant, proud athlete.
An athlete who had just been blindsided by the cruelest blow of them all.