Defense is Lakers’ downfall in loss to the Celtics

Kobe Bryant sat in his chair wearing a black robe, his feet in a bucket of ice, his answers to every question curt, yet straightforward and clear.

None of his answers were more succinct than when Bryant was asked to grade the Lakers’ defense against the Boston Celtics during Sunday’s 109-96 defeat at Staples Center.

“F,” Bryant said.

Why?

“Well, we didn’t execute well,” Bryant said. “We blew too many assignments.”

Enough to allow the Celtics to rip holes in the Lakers’ up-and-down defense.

Enough to allow the Celtics to make a whopping 60.3% of their shots against the back-to-back NBA champion Lakers.

When Lamar Odom was told how well the Celtics shot, he replied with a question.

“How much?” Odom asked, raising his eyebrows.

Um, 60.3%, Odom was told again.

“”Whew!” said Odom, shaking his head. “Sixty! They are too good to let them shot 60% from the field. You should expect to lose to the Boston Celtics if you let them shot 60%.”

So what if Odom was off by 0.3.

He made his point.

And then there was Boston’s three-point shooting against the Lakers.

The Celtics burned LA’s exterior defense, making 52.9% (nine for 17) of their three-point shots.

Boston didn’t shoot less than 50% from the field in any quarter.

The Celtics shot 68.8% from the field in the third quarter.

And they were just getting warmed up.

The Celtics blitzed the Lakers’ defense in the fourth, making a scorching 70% (14 for 20) of their shots.

So what happened to the Lakers’ defense in the fourth?

“Just mental lapses defensively,” Bryant said. “Just gave them too many looks.”

In the second half, Boston shot 69.4% from the field, 63.6% (seven for 11) from three-point range.

“I think the defense in the second half was what we’re unhappy about as far as the coaching staff,” Lakers Coach Phil Jackson said.

The porous Lakers’ defense has put them in something of a bind.

They now have the fifth-best record in the NBA.

They are 7½ games behind the San Antonio Spurs, who have the best record in the NBA at 40-7.

They are only one game ahead of the Dallas Mavericks in the Western Conference.

And even more telling, the Lakers are 3½ games behind the Celtics, who have the second-best record in the NBA at 36-11.

The Celtics’ Big Three did much of the damage.

Paul Pierce burned the Lakers for 32 points on 11-for-18 shooting, three for five on three-pointers.

Ray Allen had 21 points on eight-for-12 shooting, three for seven on three-pointers.

Kevin Garnett had 18 points on nine-for-12 shooting.

And then there was Rajon Rondo, who had a double-double with 10 points on five-for-nine shooting and 16 assists, 15 in the second half.

Ron Artest had the primary assignment of defending Pierce, something the Lakers small forward didn’t do a very good job of.

“I don’t want to take anything away from what he did today,” Artest said. “He had a good game today and I don’t want to take anything away from that.”

The Celtics had 34 assists on 44 field goals.

That was just one reason why the Lakers’ defense was in jeopardy so much.

The main reason, however, was because the Lakers just weren’t very good on defense.

“We’re an inconsistent team on defense right now,” Odom said. “We have to get back at practice and keep working on it.”

broderick.turner@latimes.com

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