BOSTON (AP) -- The abdominal strain that sidelined Kevin Garnett for nine games at midseason was probably the best chance for the rest of the NBA to catch the Celtics.
Now Garnett's back, and playing as well as he did before his injury.
"He's all the way back," Boston forward Paul Pierce said Sunday night after Garnett had his best game since returning, scoring 20 points and grabbing 16 rebounds to lead the Celtics to a 98-88 victory over the Atlanta Hawks. "Did y'all watch the game tonight?
"When he's going to the basket, inside and outside, dominating the rebounds: That's the Kevin Garnett I like to see."
Garnett never looked up.
"I had a decent night," he said, deadpan.
Pierce scored 30 points, 17 in the pivotal third quarter when Boston scored 13 straight points to take the lead for good. Ray Allen scored 17, and Kendrick Perkins had 11 points, a season-high 12 rebounds and a career-high six assists to help the Celtics win their fifth consecutive game.
"In the third quarter, the difference was Paul Pierce. He just took over," Perkins said. "I'm used to that now, but when I first got here, I was like, 'Man!' Now, it's just what Paul does."
Point guard Rajon Rondo had six points and eight assists one day before the Celtics are expected to bring in backup Sam Cassell, who was waived last week by the Los Angeles Clippers. The Celtics play the Detroit Pistons on Wednesday in a matchup of the top two teams in the East.
"People are expecting that to be the Eastern Conference finals matchup," Garnett said. "It should be a fun game."
And more fun for Garnett now that's he's healthy.
The Celtics big man strained a stomach muscle on Jan. 25 and returned on Feb. 19, eight games ago. His 20 points, 16 rebounds and 35 minutes were all his most since he's been back.
"I'm human, too, and I do have rust," he said. "I'm coming along, slowly but surely."
Josh Smith scored 20 points and added nine rebounds, and Al Horford had 14 and 11 for the Hawks, who missed a chance to move into a tie for the eighth and final playoff spot in the Eastern Conference. Mike Bibby, acquired at last week's trading deadline for a playoff push, had 14 points and nine assists.
"They're probably going to be a team that we see in the first round, a team that can play in the eight [seed] or the seventh spot," Pierce said. "He's definitely an added dimension for that team, a veteran who can give them a boost, especially in these last 20-25 games."
The Hawks led 46-41 after Bibby's alley-oop to Horford for the first basket of the second half. But Boston scored the next 13 points -- including nine in a row from Pierce -- before Smith hit a free throw with 8:42 left in the quarter.
Pierce added a jumper that gave him 11 consecutive Boston points and gave the Celtics a 58-47 lead.
"In the third quarter, we started to turn it over, Paul got a hot hand and our defense went the other way," Hawks coach Mike Woodson said. "This is a good ball club they have here in Boston."
Atlanta came within three points several times, the last at 73-70, before Eddie House hit a 3-pointer with 9:05 to play.
P.J. Brown did not dress again for the Celtics. He has not played since being signed off the street on Wednesday. ... Cassell was bought out by the Clippers on Friday and is expected to clear waivers at 6 p.m. Monday.