"I guess the story is Antoine's first half and Paul's second half," Celtics coach Jim O'Brien said. "Just an extraordinary effort from our two captains."
The Celtics are within one win of their first trip to the conference finals since 1988. They can wrap up the series with a win at Detroit on Tuesday.
"Our goals are much higher than just winning this series," Walker said. "We have to stay prepared. We have to avoid those big spurts on the road. We have to come and try and bury them on Tuesday."
Walker scored 22 of his 30 points in the first half. He was the only player who seemed to quickly shake off the rust from Friday, when the teams played the lowest-scoring playoff game in the shot clock era.
Despite Walker's first-half explosion, the Celtics only held a two-point lead at halftime. Part of that had to do with Pierce, who made just 1-of-6 shots.
But Pierce came alive in the second half, scoring 23 of his 25 points. He had nine in the third quarter, when the Celtics grabbed control for good and took a 66-58 lead into the final period.
"I had to come out and be more aggressive and be a low-post presence because they have been doing a lot of switching," Walker said. "Finally today, we got them to stop switching. By me being able to go out and be aggressive in the first early minutes of the game, allowed things to open up for Paul in the second half."
Pierce made sure the Pistons got no closer than seven points in the fourth quarter as he scored 14 points. During a stretch of 6 1/2 minutes, he scored 11 of Boston's 12 points, then blocked a shot leading to a layup by Walker that gave the Celtics an 82-71 lead with 3:54 to go.
Walker made 10-of-19 shots and 9-of-10 free throws, adding four assists. Pierce made 7-of-16 shots and 10-of-12 free throws, while collecting a playoff career-high 17 rebounds and six assists.
"When my offense is struggling, like it has been in this series, I try and do the little things to help this ballclub win," Pierce said.
"Up until this game, we'd done a pretty good job of kind of keeping those guys contained, where they're not going crazy on us," Pistons coach Rick Carlisle said. "Tonight there was a situation where those two guys did step up their offensive productivity and it's tough, but we've just got to keep hammering away at it."
As they have throughout the postseason, the Pistons again struggled on offense. They shot just 37 percent (28-of-75), committed 18 turnovers and relied too heavily on the 3-pointer, hoisting 31 and making 11.
"Once again we had 18 turnovers," said Carlisle, whose team dropped to 0-4 on the road in the postseason. "It's one thing to have 18 turnovers but when they lead to 25 points, that's a huge number. They're too often resulting in layups and easy shots."
Cliff Robinson scored 24 points and Jerry Stackhouse added 16 for Detroit, which had just 16 points in the paint. Each made four 3-pointers, with Robinson firing 10 and Stackhouse and Damon Jones seven each.
"It's tough to get quality looks and when we get quality looks, we haven't been able to knock them down," Stackhouse said.
"We've got to find a way to get some inside shots," said Pistons forward Ben Wallace, who had 21 rebounds.
Tony Delk scored 16 points for the Celtics, who shot 44 percent (31-of-71) and attempted 19 3-pointers, making six.
The Pistons missed their first eight shots of the second half as the Celtics scored 12 straight points. Pierce had five, including a 3-pointer that made it 53-39 with 8:05 left in the third quarter.
"We played good half-court defense and we were able to get out on the break," Pierce said. "We forced turnovers (to) get out on the break and get easy buckets."
Robinson scored seven straight points to cut the deficit to 58-53, but the Pistons got no closer. His 3-pointer made it 68-61 early in the final period, but Pierce came right back with a three-point play that began his dominant stretch.
Pierce had a face-up jumper and two free throws around Robinson's foul shot to push the lead to 76-65 with 5:41 remaining. He answered a pair of 3-pointers by Stackhouse with a jumper and two foul shots, keeping the margin safe at 80-71 with 4:25 to go.
Pierce blocked Stackhouse's jumper and saved the ball as it was going out of bounds. Walker went 1-on-3 but scored anyway.
"Antoine and I got caught up in a switch and they reversed the ball to Cliff Robinson, who's a great shooter," Pierce said. "I just wanted to try and bother the shot. I didn't realize I blocked the shot until I looked up and saw the ball coming down."
Detroit still had a shooting hangover from Friday, but Walker didn't. While the Pistons were making just 6-of-21 shots in the first quarter, Walker was making 6-of-8. He scored Boston's last seven points of the period, helping his team open a 21-17 lead.
"Antoine got so strong in the first half and got so many good looks that we just kept going to him," O'Brien said. "When Paul got in foul trouble and Kenny got in foul trouble,, it eliminated our pick and rolls with Kenny. And it eliminated our post-ups for Paul. So instead of Antoine getting a few touches, we just kept going at him because he had the hot hand. And he was very effective."
Delk continued the Kentucky connection in the second quarter, scoring 10 points. His 3-pointer widened the lead to 30-20 before the Pistons crawled back in it with a 12-4 surge. A 3-pointer by Stackhouse gave Detroit a 39-38 lead in the final minute, but Delk answered with one just before the horn.
In the first half, Walker (22) and Delk (15) scored all but four of Boston's points.
"Those are the two guys that pretty much carried us," Pierce said. "Antoine, he really established himself as a low-post presence and really dominated down there today. He didn't take a lot of outside shots. I could tell from the first quarter, the way he was going, that it was going to be his night."