UPDATE: In italics below are comments from Wilson.

ORIGINAL POST: Manager Bruce Bochy just told us that closer Brian Wilson underwent an MRI this morning that revealed a “mild” strain of his left oblique muscle. Wilson will be shut down until Monday, when the injury is reassessed.

Bochy tried to be reassuring, saying, “Nothing is torn or anything,” but even he had to concede concern. Obliques are tricky injuries that usually sideline pitchers for about a month. Bochy said “I can’t go there yet” when I asked if Opening Day was in doubt, but do the math. The season starts in 12 days. Moreover, he was behind from the get-go because of his early-camp back injury. He has thrown only five Cactus League innings.

“There’s concern, sure,” Bochy said. “Sometimes these things take longer than others. On Monday we’ll have a better idea, and then I can tell you how much concern, but sure there’s concern when it’s an oblique.

“We still have some time here. He was at a pretty good place before he injured it, how he was throwing. It’s a setback. Hopefully Monday we’ll find it it’s not too long of a setback. I know how tough and strong he is. He isn’t overly concerned.”

Wilson downplayed this injury completely. He told a group of reporters that included our Scott Ostler the team should not be worried about Opening Day because “they know I’ll be ready.”

“I’m fine,” he said, “just another crappy nuisance to deal with. Can’t do anything, can’t get down, can’t get mad, just treat it and be over with. On a serious note, they asked me what kind of music you want to listen to on the MRK. It’s like, I don’t care, whatever’s playing. And I kid you not, ‘Smoke on the Water’ was playing. So everything’s going to be good.”

That was Robb Nen’s entry music.

Bochy said he suspects Wilson will want to start throwing again Monday or Tuesday, but “that’s not going to be the case.”

For those seeking a bright side, there are two considerations:

One, the Giants’ bullpen is loaded with hard throwers and late-inning experience. Bochy mentioned Javier Lopez, Jeremy Affeldt and Sergio Romo as potential closers if Wilson misses any of the regular season. He also could have thrown in Santiago Casilla.

Two, Wilson will know what to expect as he recovers from this. You might recall that he strained the same oblique muscle in his first major-league inning, on April 23, 2006 at Coors Field in Denver. But he was young and stupid then, didn’t tell anyone and went out for another inning while hurt. He went on the disabled list the next day for 25 days.

He said it felt a lot worse that time than this time.

This time, he told the training staff immediately after he felt something in his most recent outing Thursday night.

In another medical note, Mark DeRosa said team doctors have advised him not to play for a few days as a precaution against tendinitis in his surgically repaired wrist. DeRosa insisted he feels no discomfort. The docs were just concerned about how many at-bats he had early in camp after so much inactivity.