Updated

GAME TIME: Lakers 90, Celtics 89

This was a rock-'em-sock-'em battle between two formidable heavyweight teams that have both been playing like lightweights as of late. Coming into the game, the Lakers were 2-5 and the Celtics were 6-10.

And when the final buzzer sounded, the Lakers took a significant step forward while the hometown Celtics continued their freefall.

WHY THE CELTICS LOST

In the second quarter, Rajon Rondo almost single-handedly rescued Boston from a double-digit deficit and enabled them to gain control of the game. His swift penetrations, full-court pushes and stop-and-go dribbles that turned the corner of virtually every high screen-and-roll were impossible for the Lakers to contain. Layups, kick-out assists and drawing fouls -- Rondo had the game in his pocket. Of his game total of 12 assists, 10 were dealt in the first half.

But from the middle of the third quarter on, Doc Rivers chose to put the offense in the hands of Paul Pierce . He did this even though L.A. still hadn't figured out a way to deal with Rondo -- the visitor's switches were just as futile after the intermission as they were in the initial half. While Pierce did grunt out 15 points on 4-for-11 shooting, Boston's offense slowed down and the ball was rarely reversed.

Late in the fourth quarter, Rondo's frustration showed when he forced several shots and made several off-target passes.

It was a costly change of offensive emphasis by Rivers and his staff.

While Kevin Garnett attacked the basket with success on two early sequences and tallied one of his patented low-post spinners, he spent the rest of the game mostly shooting jumpers. Overall, he went only 4-for-11 on his mid- and long-range springers. More post-up opportunities and baseline isolations for Garnett would have been beneficial.

As ever, Kendrick Perkins simply didn't get enough touches in the pivot -- especially when compared with the number of opportunities granted to Andrew Bynum (13 shots to seven). Why not give Perkins more ball-time and try to put some foul trouble on Pau Gasol and Bynum?

Tony Allen was also instrumental in changing the ballgame after Boston's opening gambit of playing bang-and-slam basketball failed. Sure, Allen missed three layups, but he also aggressively drove the ball into the paint, often catching L.A.'s defense off-balance. More importantly, he did an admirable job of making Kobe work hard to even see the rim. But Allen didn't get enough daylight late in the game.

Ray Allen couldn't shoot himself in the foot from close range. His defense was uncommonly adequate, but his 2-for-10 shooting made him an overall liability.

Glen "Little Adult" Davis hustled and bustled as usual, but on one key play, he lazily went under a high screen and permitted Lamar Odom to hit a wide open three-pointer that stung the Celtics.

The Celtics did play excellent team defense that reduced the Lakers to one-on-one offense in the endgame. But Rasheed Wallace , Garnett and Perkins were each guilty of late rotations that allowed the Lakers a trio of uncontested layups.

Bad passes and even worse reception attempts accounted for most of Boston's 18 turnovers: Garnett had five of these, Pierce had four and Rondo compiled three. And when anybody except Rondo had the ball on a string, the offense was anything but crisp.

Championship teams do not get outscored 24-16 in the last quarter at home against elite teams like the Lakers. Boston had trouble maintaining its concentration, made far too many costly mistakes and managed to snatch defeat from the jaws of victory.

WHY THE LAKERS WON

Kobe Bryant did as he usually does. This time, it was nailing a twisting, fading 15-footer under Ray Allen's heavy pressure with 7.3 seconds left in the game for the eventual winner.

Before his latest miracle, Kobe was effectively stymied by Boston's double-teaming defense. The Celtics' biggest defensive surprise was sending Perkins to two-time Bryant. As a result, Kobe had one jumper blocked, shot an airball and committed an offensive foul. Although Kobe scored a measly 19 points on 8-for-20 shooting and recorded six assists and four turnovers, he proved once again that when is more important than how many.

Andrew Bynum made several errors -- including three missed layups -- but he proved to be too quick and too long for Perkins, Wallace or Garnett to consistently defend. Screen-and-roll dunkers, put-backs, flip shots and baby jumpers were all showcased by the young man on his way to 19 big points on 7-for-13 shooting.

Ron Artest looked slightly more nimble than in recent games. He played his familiar rough-tough defense against Pierce and even carried the offense for a short stretch late in the third quarter.

Pau Gasol had only four makes (in nine attempts), missed several easy shots, scored a mere 11 points, had twice as many turnovers (four) as assists and was routinely bounced around by the bullying tactics of Wallace and Perkins. Indeed, for most of the endgame, Gasol sat and watched Bynum play.

But Gasol pulled down 11 rebounds and made several expert baseline rotations.

Jordan Farmar and Shannon Brown provided sparks off the bench at both ends of the court. Between them, they shot 6-for-8 and shared 14 points. Their speed and quickness were absolutely necessary since Derek Fisher -- who shot well -- caught nothing but a cold in chasing Rondo.

The Lakers had to overcome numerous insufficiencies to pull the game out of the fire:

• Even though Rondo hit only one of his four jumpers, the Lakers never went under any high screen-and-rolls that involved him.

• Their perimeter shooting was abysmal: 4-for-14 from the promised land.

• Their triangle offense flat-lined late in the game.

Even so, they made they plays they had to make. And Boston didn't.

And Kobe in a win-or-lose situation is money.