Pau Gasol’s injury is a new strain for Lakers

If it feels as if the Lakers have been here before, it’s because they have.

The Pau Gasol hamstring watch began its second engagement Monday when the Lakers forward-center was deemed doubtful for tonight’s game against the Houston Rockets because of a mild to moderate strain in his left hamstring.

If Lakers followers sighed, it was understandable, seeing how Gasol sat out the first 11 games of the season because of a strained right hamstring that was similarly labeled day to day but dragged on for almost six weeks and included two attempts to practice followed by flare-ups, and setbacks, the next day.

A little more than six weeks after returning, Gasol checked out of Sunday’s game after seven minutes against Dallas and checked in to see team doctor Steve Lombardo on Monday morning.

Results of an ultrasound and MRI exam showed the strain, one of many injury-news items Monday. (Quick recap: Ron Artest went through a full practice and will probably play tonight if he feels fine this morning, Luke Walton went through a limited part of practice and won’t play until later this week at the earliest, and Lamar Odom missed practice because of intestinal flu symptoms but will probably play tonight.)

Hamstrings have become a major issue for the 29-year-old Gasol, who just signed a three-year, $57-million extension that would keep him under contract through 2013-14.

“I don’t know what we can do,” Lakers Coach Phil Jackson said. “He never felt any unusual sensations or regulation in his running [before Sunday’s game]. Warmed up and stretched the normal way he does. It was just something very unusual.

“We’ll have to do much more intensive research on this now. It’s not related to exercise or an activity that creates this.”

Gasol was not available to reporters Monday, and Jackson was coy when asked how Gasol was injured.

“It happened before the game in a very unusual way and I’ll let Pau explain that to you when you see him,” Jackson said. “You have to ask him. He told me the story, so I’m just expecting him to tell you.”

There’s not much to it. Gasol apparently felt a twinge in his hamstring while jumping up and down to get loose a few minutes before the game.

Then he tried to play.

“There have been many times that Pau has said that he’ll feel a little hang-up in his hamstrings during the course of the year,” Jackson said. “When he said it at this juncture before the game, we said, ‘Well, we’ll see how he goes at the start’ as we normally do.”

Gasol had six points and two rebounds before leaving. He is averaging 16.8 points, 11.5 rebounds and 3.4 assists.

As Gasol exits for at least tonight’s game (“doubtful” in Lakers medical jargon often means “out”), Artest will probably return after missing five games because of a concussion.

Artest went through an entire practice Monday with contact, had no complaints and will be reevaluated after this morning’s shoot-around.

“It felt really good,” Artest said. “It’s up to Phil. I don’t want to put words in his mouth.”

Jackson said, “We sure want him in there.”

In addition to a concussion, Artest had four staples in the back of his head and about seven stitches in his left elbow because of lacerations from what he said was a fall at his home on Christmas.

“I felt like I’ve got to get back in shape, but that’s like everybody,” Artest said. “You know, you’re out for a while and you come back and you’re not in shape. It’s not like I’m the first person it’s happened to.”

If Odom comes back healthy after a one-day absence, the Lakers’ frontcourt tonight will probably be Andrew Bynum, Artest and Odom.

At the end of a long medical day, there was Walton, who participated in non-contact parts of practice and hoped to take part in a full practice Thursday after being out almost eight weeks because of a pinched nerve in his back.

“The worst part was obviously the conditioning and my legs from not playing in five, six weeks, however long it’s been, but my back felt really good,” Walton said.

Etc.

Jackson seemed to long for Artest’s return: “The one thing you can really count on Ron for is that he’s going to give you a one-on-one effort against a scorer probably better than anybody else can do in the league right now,” he said. . . . Would Kobe Bryant put up more shots if Gasol missed an extended period? “More than I’ve been already?” he said with a smile. “I’ll go out and play and do my usual.”

mike.bresnahan@latimes.com

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