SCOTTSDALE, Ariz. -- Baseball's all-time saves leader is the latest Brewer to be shut down with a rib-cage injury, leaving the manager a bit concerned about who would take the ball for the ninth inning if Trevor Hoffman cannot.

Hoffman, the 41-year-old right-hander, was bumped from a scheduled appearance over the weekend and will miss a few more days with a strained muscle in his right side, Brewers manager Ken Macha said Tuesday. The news came a day after starter Braden Looper, Milwaukee's only other major free-agent pickup, pitched a Minor League game for the first time since he suffered his own rib injury.

Together, Hoffman and Looper will take up at least $10.75 million of Milwaukee's payroll, which projects for the neighborhood of $85 million-$90 million. But Looper is back on track to be ready for the start of the season, and pitching coach Billy Castro believes Hoffman will be, too.

"[Hoffman] doesn't need that many innings," Castro said. "He knows what he's doing to get ready and when the bell rings, I think he will be ready. We're only halfway through Spring Training right now. We forget that there are 10 extra days. I think he'll be fine."

Muscle strains are graded from 1-3 based on severity. Hoffman has a Grade 1 strain of his right oblique, the least severe of the three.

He has logged three one-inning outings in Cactus League play and made another appearance in the bullpen. He last pitched Friday against the Royals and felt some soreness in his side the next morning on his drive to the ballpark, according to Macha.

The Brewers are taking an extra-cautious approach with Hoffman, who signed a one-year deal with a $6 million base salary.

"If this were the last week of camp, you would be more concerned," assistant general manager Gord Ash said. "There's no urgency to push him right now."

The Brewers do not open the regular season until April 7 in San Francisco.

A healthy Hoffman would help ease Macha's concerns about the bullpen, especially after Carlos Villanueva surrendered five runs on five hits, including a pair of home runs, in 1 1/3 innings against the Giants on Tuesday.

One of the homers was an inside-the-park shot aided by Minor League left fielder Brendan Katin, who didn't converge on a ball hit off the center-field wall. But the other was more than legitimate, a booming two-run homer in the bottom of the ninth inning by Jesus Guzman that cleared the 30-foot-tall batter's eye that sits 430 feet from home plate and gave the Giants a 7-5 win.

"This guy here, Villanueva, has had one good outing all spring, as far as I'm concerned," Macha said. "The other outings he's pitched just a single inning and been mid- to high-20s with his pitches. ... He's throwing a lot of pitches and not being able to put the guy away. Now, when you get to pitch [No.] 25, 26, you're going to leave something over the plate and that's what happens.

"I'll talk to him [Wednesday], maybe talk to Billy and see what our plan of attack is. With Hoffman down, I asked Billy, 'Who's your closer if he can't go?' He answered, [Villanueva]. I said, 'Well, he hasn't had any good outings this spring.' Now you have to look at what your alternatives might be."

In other Brewers injury news:

• General manager Doug Melvin spoke Tuesday with left fielder Ryan Braun, who tweaked a rib-cage muscle in his lower back during Team USA's World Baseball Classic win over The Netherlands on Sunday. Braun will not play Tuesday night against Puerto Rico, an elimination game for the Americans, but reported feeling better.

"He feels much better, like this is very minor," Ash said. "Just for caution's sake, he will not work out [Tuesday] and will not play."

If Team USA wins Tuesday night and advances to the final round in Los Angeles, Braun will remain with the team. There was some discussion of bringing him to Phoenix for an examination with Brewers doctors, but the pit stop was deemed unnecessary.

• Mike Rivera, the backup to Brewers catcher Jason Kendall, is scheduled to start Wednesday's game in Tucson against the Diamondbacks. He has been sidelined since straining his right hamstring in baserunning drills on March 5.

• Another catcher, Angel Salome, remains out indefinitely with a lower back strain. He's likely ticketed for Triple-A Nashville but is considered Milwaukee's top prospect at that position.

• Outfielder Tony Gwynn Jr. remains on a program to strengthen his strained right shoulder and is penciled in to play in the field for the first time this weekend, Macha said.