He may need to step up even more with Paul Pierce banged up, too.
Green, who burst onto the scene with a career-high 43 points against Miami on March 18, came up huge again Wednesday in a 98-93 win over Detroit. The former Georgetown standout posted 34 points, six rebounds and four blocks as Boston (39-36) clinched its sixth consecutive postseason berth.
"I don't try to take over games. We have 'the Truth,'" said Green, calling Pierce by his nickname. "We feed off each other. If it's in my hands, I try to make a play. If it's in his hands, he'll try to make a play. We're playing off each other."
Averaging 23.8 points on 56.8 percent shooting over the last five games, Green has started seven straight contests and nine of 11 with Garnett sidelined by an ankle problem, and he may stay in the starting lineup even when Garnett returns.
Green could be asked to take on an even bigger load Friday with Pierce uncertain to play due to a sore right ankle.
"You have seen a lot of flashes of that this year," Pierce said of Green becoming a go-to option. "You've got a guy like Jeff who can put up big numbers like that, who can take over like that. It's fun, it's fun to watch and to be a part of."
The Celtics sit in seventh place in the Eastern Conference and, though unlikely, have a chance to finish as high as fourth.
"We knew we were a playoff team before the season started, despite the injuries and everything," Pierce said.
"The playoffs is a totally different game; it's nothing like the regular season. At least these guys will go out there and get their feet wet, see some shots go in, rebound the ball and get some experience."
The Celtics now turn their attention to the Cavaliers (22-52), who have been outscored by an average of 13.5 points during a 10-game skid - their longest since dropping an NBA-worst 26 straight in 2010-11.
Cleveland's woes continued Wednesday with a 113-95 loss to Brooklyn. The Cavaliers trailed by as many as 34 points and allowed the Nets to shoot a season-high 56.6 percent.
"We just didn't show any life," coach Byron Scott said. "The energy, the effort wasn't there - for whatever reason."
Playing for the second time in three games after missing eight with a shoulder injury, Kyrie Irving was held to 16 points on 5-of-16 shooting.
"Have I checked out? No," said Irving, averaging a team-high 23.0 points. "I'm out here playing with basically still a sprained AC joint and with not a care in the world because I just want to play. I haven't checked out. That thought has never crossed my mind."
Irving is averaging 26.0 points in five career meetings against the Celtics, tied for his second-highest mark against any opponent. He scored 40 in a 95-90 win Jan. 22, but he missed a 93-92 loss March 27. Green scored 21 points that night, including the game-winning layup as time expired.
Cleveland has lost eight of 10 in Boston, where the Celtics have won 13 of 15 overall.