Sometimes when the Boston Celtics flirt with danger, it finds them, smacks them and attempts to teach them that danger is nothing desirable. Other times when the Celtics flirt with danger, Brandon Bass scores 18 points in a single quarter to deliver them from evil and into a commanding 3-2 series lead.

Little Bass had done before Monday night foreshadowed his eruption. He had played 69 games with the Celtics, including both regular season and the playoffs, and scored 18 or more points in a full game just 11 times. His season high of 22 points, which he accomplished twice, came against the Golden St. Warriors and the Charlotte Bobcats, two of the league’s worst defenses. He had not scored more than 15 points in any playoff game, and he had struggled with his shot, including a 5-for-15 showing in Game 2 against Philadelphia that featured an impressive nine straight misses.

Asked what the difference was Monday, when Bass finished with a postseason career-high 27 points, including 18 in the third quarter (two more than the Sixers mustered), Doc Rivers began, “Well, the ball went in. That was one.”

That was one ingredient of the recipe, but the story was far more complicated than that. It included a point guard, Rajon Rondo, who found Bass when he opened and hit him in stride. It included a Philadelphia 76ers defense designed to limit Paul Pierce and force the ball to Boston’s big men. It included Bass reading and reacting intelligently to Philadelphia’s coverage.

As Rivers explained, “One of the things we keep trying to get Brandon to do is get to the second pick. He’s open on the first one, but they recover out. But then when he swings it and gets to the second one, we keep telling him, ‘How many bigs want to show twice on the same pick and roll, and then recover back out to you? And if they recover back out to you, they’re out of control and you can shoot or drive.’ And I just thought he kept the game simple in the second half.”

Added Ray Allen, “I guarantee he will tell you it was one of the more difficult games he had to play. He was in great position all night, he read the defense, and made the right plays offensively the whole time.”

None of Bass’ contributions were more important than those at the end of the third quarter. Kevin Garnett was subbed out of the lineup with five minutes left in the frame, and the Sixers quickly cut a 63-57 deficit to 63-62. At that point, the Sixers felt they had quelled the momentum.

“I thought okay guys, we’re back in it,” said Collins.

But Bass had other plans. He drilled a 15-footer on Boston’s next possession, dunked on the following one, and finished with eight points in the final 3:33 of the third. By the time the fourth quarter arrived, the Celtics held a comfortable lead, 75-66. Not only had they fended off their normal lapse when Garnett hits the bench, they even boosted the lead without him on the floor.

After paving the way as Boston avoided what might have been a lethal loss, Bass sat at the press conference podium and pointed out the beads of sweat on his forehead.

“Because I’m nervous,” he explained. This was his first time ever sitting at a podium. “But I’m grateful.”

The Celtics were grateful, too. Without Bass’ third-quarter explosion, they might be staring at potential elimination Wednesday night. Instead, they’re one win away from the Eastern Conference Finals.