Boston Celtics' Paul Pierce, centre, led his team with 28 points in Game 2 of the NBA final on Sunday. (Winslow Townson/Associated Press)

The rumours of Paul Pierce's demise may have been grossly exaggerated.

Pierce's strained knee appeared to be just fine on Sunday as his 28 points helped the Boston Celtics to a 108-102 win over the visiting Los Angeles Lakers in Game 2 of the NBA final.

Pierce was ruled as questionable after straining his knee and being carried off in the fourth quarter of Game 1, but he was a force on Sunday — adding eight assists and four rebounds in the win.

Little-used reserve Leon Powe came off the bench to have the game of his career with 21 points in just 15 minutes for the Celtics.

Ray Allen and Kevin Garnett each earned 17 points with Garnett also hauling down 14 rebounds. Point guard Rajon Rondo chipped in with a career-high 16 assists.

Kobe Bryant scored 30 points to lead Los Angeles, including 13 in a furious fourth-quarter rally that saw the Lakers cut a 24-point deficit to just two points with 38 seconds remaining.

But Pierce hit a pair of free throws and had a crucial block on three-point attempt by Sasha Vujacic at the other end of the floor.

James Posey then sealed the win at the line with another pair of free throws for Boston, which leads the best-of-seven series 2-0.

"We're happy because we won, but we definitely learned a lesson," Pierce said.

Despite the loss, Bryant felt that the Lakers might have also learned something.

"It's something that we can take from," Bryant said of the rally. "We played with a sense of desperation and aggression. I think that's something to take home and learn from."

Pau Gasol had 17 points and 10 rebounds and Vladimir Radmanovic also added a double-double of 13 points and 10 rebounds in the Lakers loss. Lamar Odom had 10 points and eight rebounds, but fouled out of the game late in the third quarter.

Boston was helped significantly by free-throw shooting on Sunday — hitting 27 of their 38 attempts. The Lakers were perfect from the line, but had just 10 attempts.

The series will now shift to Los Angeles for the next three games, with Game 3 going Tuesday (6 p.m. PT). Only three teams have ever recovered from the 2-0 deficit to win the final, but the Lakers have gone a perfect 8-0 at Staples Center in the post-season, with their last home loss dating back to the regular season on March 28.

"We've come too far to really sweat being down 2-0," Bryant said. "We're going to go home and handle our business."

Bryant brilliant late

With 2:53 to play, Bryant quickly rattled off seven straight points to cut the lead to just 102-95.

The Celtics appeared almost stunned as Sasha Vujacic then hit a three, followed by a steal and dunk from Radmanovic that trimmed Boston's advantage to 104-100.

Bryant then hit two from the line to pull the Lakers within a basket before Pierce revived his team from its funk.

He drew a foul on an aggressive drive to the rim, hit his free throws and followed that up with some sparkling defence with his block on Vujacic with only 14 seconds remaining.

"I had an open look, he kind of jumped out of nowhere," said Vujacic. "I took the shot, I felt good about it. He blocked it. It could have gone in or gone out. He blocked it."

Foul trouble dogs Bryant early

In the Lakers' four losses to the Celtics this season, Bryant in particular has struggled — shooting just 35-93 from the field. He shot an improved 11-23 from the floor in Game 2, but got off to a slow start early on.

He missed his first two shots, including an easy layup underneath, and didn't appear to get the looks he wanted against the Celtics vaunted defence.

Bryant was just 1-4 from the floor when he was forced to the bench with his second foul with two minutes remaining in the quarter.

Despite their superstar's struggles, the Lakers took a 22-20 lead into the second after Jordan Farmar's three-pointer with three seconds remaining.

Boston came out firing in the second quarter as their reserves led the way during a 10-0 run.

Powe scored five of those points on free throws, veteran P.J. Brown added a jumper and Pierce capped the run with a three to give Boston a 30-22 lead.

The Lakers began cutting into the Celtics' cushion, pulling to within 41-37 on a three-point play from Gasol.

But Pierce and Allen hit back-to-back threes to kick-start a 13-5 Celtics run that saw their halftime lead balloon to 54-42.

Boston kept the pressure on in the third quarter, using a late 15-2 run to put the game seemingly out of reach.

Pierce started the run with a jumper and a reverse layup, while Powe continued his remarkable run with an alley-oop and two dunks to put Boston up 83-61 with 12 minutes to play.

Powe, who barely saw the floor during the Celtics' drive to the playoffs, continued to play the role of X factor in the fourth with another six points.

His play was so strong that he had the Boston faithful modifying the familiar chant of "Beat L.A." in favour of "Le-on Powe!"

"He was terrific," Celtics coach Doc Rivers said.

With files from the Associated Press