When Wily Peralta starts, the Brewers have found a way to keep at least one of their big bats in the lineup. Jonathan Lucroy, Milwaukee's regular catcher and RBI leader, will make his second start at first base Tuesday, while backup catcher Martin Maldonado takes his usual place behind home plate when Peralta toes the rubber.
With Ryan Braun suspended and Aramis Ramirez and Corey Hart injured, Lucroy's bat becomes more important to the Brewers' lineup, so he volunteered last week at Wrigley Field to play a position he had little experience with outside of a few innings earlier this season.
He was charged with an error on a short-hopper during the Brewers' 6-1 loss to the Cubs on Wednesday, but generally handled himself well.
"If he matches up against somebody well and it's a day I think it's right for him to do it, then I'll put him at first base," Brewers manager Ron Roenicke said.
Chalk Tuesday up as one of those days. Lucroy is 6-for-15 lifetime against Giants starter Matt Cain with a double, a triple and a home run. Lucroy also enters Tuesday batting .327 over his previous 62 games, boosting his average from .208 to .284. He leads the Brewers with 59 RBIs and is second with 16 home runs.
Of his only other Major League start at first base, Lucroy said, "Other than the one error, I thought it went all right. I'm just going to try to keep the ball in front of me. I'll get better at it."
Lucroy has not been taking grounders at first base on the days he starts at catcher to avoid beating up his body. Next year in Spring Training, he plans to spend much more time learning the position.
Cain will try to keep his recent roll going for the Giants, who won Monday's series opener, 4-2. He has two wins in his last three starts with a 1.80 ERA and 18 strikeouts in 20 innings. He brings a 4.57 ERA -- the highest of his nine-year career -- and a 7-6 record into Tuesday, but without the four outings in which he allowed seven runs or more, Cain's ERA would be 2.76.
Brewers: Peralta aims to regain form
Peralta allowed just one earned run in his first four July starts (0.31 ERA) but coughed up 12 runs, eight of them earned, in his last two (8.31 ERA).
The 24-year-old right-hander has shown signs of brilliance in his first full season, but has also had his share of growing pains. He brings a 7-11 record and 4.57 ERA into his 24th start Tuesday.
• Roenicke laid out plans for the returns of Yovani Gallardo, who is on the 15-day disabled list with a strained left hamstring, and Ramirez, who is on the 15-day DL with a sprained left knee.
Gallardo played long toss Saturday and is expected to throw off a mound later this week. Roenicke said Gallardo is tentatively scheduled to be activated Aug. 16 against the Reds, the day after he is eligible.
"He should fall right back into that rotation," Roenicke said.
Ramirez tested his sprained left knee on the bases Monday and, assuming no setback, will do the same Wednesday. Ramirez has been bothered by the knee all season but is planning on being the Brewers' designated hitter this weekend in Seattle.
Giants: Vogelsong to return to rotation Friday
Ryan Vogelsong will make his first start since fracturing his right pinkie Friday against the Orioles at AT&T Park.
Vogelsong missed more than two months after he was hit by a pitch from Washington's Craig Stammen on May 20. The right-hander made four rehab appearances with Double-A Richmond, allowing three runs in 15 2/3 innings for a 1.72 ERA. He pitched six solid innings in his final outing Sunday, allowing one run on five hits in Richmond's 8-3 win over New Hampshire.
The Giants considered assigning Vogelsong to one more rehab start, but manager Bruce Bochy said his right-hander's final 85-pitch performance convinced the team he was ready to return.
"More than anything, how he came out of it, how good he feels and the number of pitches he threw," said Bochy, who added that Vogelsong probably can elevate his pitch count to 100 if necessary against the Orioles.
Vogelsong said that he's throwing all of his pitches pain-free.
• Peralta allowed six runs (five earned) on seven hits in four innings against the Giants on April 16, his only career start against San Francisco. Cain is 3-6 with a 5.05 ERA in his career against the Brewers.
• The Brewers enter Tuesday 3-1 this season against the Giants and 11-19 against the National League West. The Giants are 8-19 against the NL Central.
Kevin Massoth is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.