NBA

Lakers run roughshod over Knicks

LOS ANGELES — Amar’e Stoudemire was excused from Saturday’s practice at UCLA to stay back in Phoenix with his family. Then he seemed to excuse himself from the first half of last night’s game against the Lakers.

Even with Andrew Bynum’s controversial ejection in opening minute of the fourth quarter, Stoudemire and the undersized Knicks couldn’t capitalize and the defending champion Lakers posted a 109-87 victory at the Staples Center, ending the Knicks’ three-game winning streak.

It was an uneven outing for Stoudemire, out of sync early with coach Mike D’Antoni blaming it on the possible emotional high from the Phoenix romp.

Stoudemire was 1 of 10 in the first half, even accidentally tipping in a missed Lakers shot, and allowed the 7-foot Bynum to score inside easily.

Stoudemire rallied the second half, scoring 18 of his 23 points with 10 boards but was a disastrous 7 of 24 overall.

Bynum had 18 points and 7 rebounds in 25 minutes before he was ejected with 11:26 left. Stoudemire blocked six shots but showed he is too undersized to be a dynamite post defender against quality centers such as Bynum.

D’Antoni made references to a Phoenix letdown.

“I just didn’t think we were sharp,” he said. “I was a little worried after Phoenix having an emotional letdown and I think we did. Although this is L.A., they shouldn’t have but we did.”

Asked specifically about Stoudemire, D’Antoni said, “Every once in a while he’s going to have an off game. I thought probably emotionally you get too high. In Phoenix we got high for different reasons, especially Amar’e and myself.”

With owner James Dolan sitting baseline, the Knicks showed their lack of size is a desperate issue against tall clubs such as the Lakers.

The Knicks (21-15), who face Portland tomorrow, were murdered on the boards, 61-42. They are still without Danilo Gallinari (knee), and Shawne Williams started in his stead.

In a terrific outing, Bynum posterized Stoudemire late in the third quarter in the night’s signature moment. Bynum caught a deep entry pass in the purple paint, turned and dunked the ball on Stoudemire — a new Laker poster instantly created.

It wasn’t soon after referee Leon Wood tossed Bynum for arguing a ticky-tack foul call on Stoudemire, unable to guard him most of the night.

“He goes a great job of getting position right under the basket,” Stoudemire said. “That’s where he scores, five feet from the basket. I made him a little uncomfortable, but he got going when he got close to the basket.”

Asked if he felt the Knicks would win after Bynum was ejected, Stoudemire said, “Not at all. I wanted Bynum to stay in. I wanted to face them when they are full strength.”

The downtown L.A. arena was packed with celebrities, including Lindsay Lohan sitting courtside in a Knicks hat. Amidst all the regulars, Jack Nicholson, Denzel Washington, Adam Sandler and George Lopez, Spike Lee was seen in his orange throwback Landry Fields jersey, bouncing up and down throughout the game, and getting booed roundly when showed on the scoreboard screen.

Kobe Bryant, after a slow start with Fields defending him well early, wound up with 27 points but shot just 10 of 28. He was Fields’ boyhood idol growing up in nearby Long Beach. Pau Gasol had 20 points and 14 rebounds.

“We’re a little bigger than they are, so there was a lot of bumping going on,” Kobe said.

The Knicks’ high-powered attack shot just 36 percent.

“There’s not too many nights we won’t shoot the ball well and tonight was one of them,” Stoudemire said.

Said D’Antoni, “We just didn’t have that right energy, toughness that we’ll have the next time we play them.”

Bynum was called for a foul on a driving Stoudemire and reacted in horror, picking up a technical. Then Bynum kept arguing, appearing to say, “Are you serious?” before he got his second T. Wilson Chandler hit two technicals and Stoudemire made 1 of 2, cutting the Lakers’ lead to 81-73.

Lakers coach Phil Jackson defended Bynum.

“He obviously felt he got fouled two or three times at the other end, then a simple thing like that was called,” he said. “I suppose it made him irritable.”

D’Antoni became so desperate that during a timeout, he tried to get the referees to issue a technical foul on Bryant, who had reacted in a shocked, theatrical manner after an out-of-bounds call went to the Knicks.

The Knicks had slashed the deficit to eight points, partly due to Ron Artest’s flagrant foul on Stoudemire. On a drive to the hole, Artest jerked Stoudemire down by the neck. Stoudemire rose up to go after Artest but they were kept separated.

“I love it,” Stoudemire said of the game’s physical nature. “It fuels me and get me going. I’m glad. The first half wasn’t that physical. Second half it was and I got going.”

The Knicks had an energetic star, with Stoudemire, Chandler and Williams notching blocks midway through the first quarter and an unusually animated Jackson calling an early timeout.

The Knicks had five blocks for the first period and took an early 10-4 lead before falling behind by 25-21 after one. They had just one offensive rebound in the quarter and it set the tone.

The Lakers finished with 17 offensive boards to the Knicks’ seven.

“You know the size. I can read the roster,” D’Antoni said.

Fields defended his childhood idol brilliantly in the first quarter, as Bryant had just two points on 1-of-4 shooting.

Fields was a force on the offensive end, too, scoring on a vicious putback dunk and hitting a couple of 3-pointers. He finished with 12 points and eight rebounds.

marc.berman@nypost.com