BOSTON –– Faced with the biggest game of their brief careers with the Celtics, neither Ray Allen nor Kevin Garnett could sleep very much Saturday night.

With the pressure and expectation of a Game Seven weighing on their minds, the Celtics’ two newest stars let all sorts of thoughts scramble their brains. Allen said that when he couldn’t let his team’s precarious situation leave his head, he got out of bed around midnight and contacted several teammates via text message.

“When I got here this morning I had to ask to make sure my attempts weren’t futile,” Allen said. “They were encouragement texts, just letting them know that I was thinking about what was going to happen (yesterday) and just making sure everybody knew about all the great things we have done all season.”

Garnett received one of Allen’s text messages. That only added to his late night.

“I haven’t slept, so I should get some sleep tonight,” Garnett said after yesterday’s dominant 99-65 win. “I’ve been up for damn near 24 hours just thinking about Game Six and the things we need to do.”

Other Celtics, including Rajon Rondo, also couldn’t sleep. Celtics coach Doc Rivers had no such problem.

“I had a little side meeting with (Garnett) before the game and he told me he hadn’t slept. I told him I slept 10 hours. I took an Ambien and I was out like a rock. It was great,” Rivers said.

Rivers said he could sense that several of his players were tense, so he made sure to talk to many of them before the game.

“I had several (meetings), not just Kevin,” said Rivers. “I was just checking in. Just wanted everybody to know that we were going to win the game and that we were OK. Just don’t try to do anything more than what you’ve done. Play your role and don’t try to be Superman tonight. … I’ve seen it happen so much where guys come into these big games and try to be something they’re not. I didn’t want anybody to do that.”

Quiet time

Paul Pierce addressed the media for the first time since he was fined $25,000 before Game Four after making a menacing hand gesture toward the Hawks’ Al Horford late in Game Three.

“With the stuff that was going on with myself, I just didn’t want to be a distraction to what we’re trying to accomplish, said Pierce. “I just needed to take a step back and not be a distraction to others with everything going on off the court.”

Above the rim

The Celtics have enjoyed plenty of success in Game Sevens over the years. They improved to 18-5 with yesterday’s win. The last lost came in the franchise’s previous Game Seven, a 97-70 thrashing at the hands of the Indiana Pacers in 2005 at the Garden. … The Celts and Cavs will play at 8 p.m. tomorrow and 7 p.m. Thursday. A limited amount of tickets for both games went on sale last night. … Rivers said he watched some film of Cleveland late Saturday but the crunch to prepare for a series with one-day’s rest will be a challenge for the coaching staff. The Celtics will hold a light workout late today.

kmcnamar@projo.com