Pierce scored 29 points, Garnett had 22 and Boston cruised to its third straight lopsided victory at home, 109-97 over the New York Knicks on Wednesday night.
"They're going to have their ups and downs," Rivers said, "and then we're going to have nights like this, too. And I'm starting to hope that we have more of these and more of these."
Pierce and Garnett have battled injuries in the second half of the season. But in the 10 games they've played together since Pierce missed three with a sore right thumb, they never combined for more than 39 points until Wednesday.
Pierce hit 11 of 17 shots despite missing nearly the entire first quarter with two fouls and Garnett went 9 for 11. Each played just 24 minutes and all five starters spent the entire fourth quarter on the bench for the third straight home game.
"We focus on our turnovers being down. We focus on our blocked shots and our rebounds. Other than that, our scoring is going to come from different places [each] night," Garnett said. "I ran the floor as good as I've been doing this year."
The Celtics led 32-19 after the first quarter, 68-49 at halftime and 92-69 after the third. Garnett's jumper with 5:26 left in the second quarter gave them a 48-37 lead and they stayed ahead by double figures the rest of the way. Pierce's basket midway through the third quarter gave Boston its biggest lead, 81-54.
"There were a lot of toos out there," New York coach Mike D'Antoni said. "They were too big, too quick, too good, and the road trip a little too long."
The Knicks had won their previous two games on the road and finished the trip at 2-3.
Boston's blowouts all came against struggling teams -- 122-103 over Indiana and 119-93 over Detroit before the victory over the Knicks. But those first two wins were interrupted by a 104-93 loss at Cleveland, an indication that the Celtics may be improving but aren't good enough to beat the best in the Eastern Conference.
The Celtics moved into a third-place tie in the East with Atlanta, which lost to Toronto on Wednesday night. But now they start a tough trip to Houston, Dallas and Utah.
"You've definitely got to take care of the games at home just to get the momentum," Garnett said. "Now we just have to go on the road, play the same way we've been playing -- sharing the ball, playing defense with a lot of energy and playing through for 48 minutes."
On Wednesday they dominated from the start and kept connecting as the Knicks kept allowing uncontested jumpers and layups.
The Knicks missed their first seven shots before Lee's layup cut the lead to 9-4. Garnett sank his first six shots before finally missing with 3:15 left in the second quarter with the score 50-37.
Then Boston expanded the lead by making 3-pointers on three consecutive baskets -- by Pierce, Ray Allen and Pierce again -- that made it 61-44.
Lee hit the first basket of the third quarter, but Boston went on a 13-3 run and took its biggest lead, 81-54 on Pierce's 15-foot fadeaway with 7:16 to go.
"They take their time on offense. They know where they want to get," said Bill Walker, who was traded by the Celtics to the Knicks on Feb. 18. "They know they're bigger and taller than us. So they were going inside a lot to" Garnett.
Pierce missed all of the first quarter after picking up his second foul just 1:51 into the game. He returned with 10:55 left in the second and had 13 points in the quarter.
"Paul and Kevin create their shots anytime on the court," Rajon Rondo said. "Get them looks. And transitions, I think, is key."
Rondo had 12 assists in just 27 minutes and tied Bob Cousy for fifth place among Celtics players for assists in one season with 642. Cousy did it in 1954-55.
Former Celtics G Eddie House missed the game with a sore right Achilles' tendon. Wilson Chandler sat out for the Knicks with a sore left groin. ... The Celtics are 3-0 against the Knicks with one meeting left April 6 in New York. ... Boston's reserves scored 35 points two nights after getting 61 against Detroit.
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