Manager Ken Macha realizes he must conserve his perfect closer.
The 41-year-old Hoffman is 8 for 8 in save chances and hasn't allowed a run in nine innings since returning from a strained right side muscle that kept him out for the first 17 games of the season. Macha gave Hoffman a breather well before the rain came because he had pitched in three straight games -- getting a save in each -- for the first time.
"Take a look at our record after 17 games and take a look at our record after that, that's how valuable this guy is," Macha said.
The Brewers were 8-9 when Hoffman returned. They are 13-4 since.
Macha spotted a scoreboard advertisement for Tums to further his point, adding "If I get him hurt, I'll be taking a lot of those."
Colby Rasmus of the Cardinals lost a two-run homer to the rain.
The game will be made up Monday night, which had been an open date for both teams. The rainout was only the fifth at four-year-old Busch Stadium and the first since March 31, 2008.
Before Hoffman's run of three appearances in three days, Macha said he intentionally didn't use his closer a few times after pitching in two straight games. Macha said all but one of Hoffman's appearances have lasted 15 or fewer pitches.
"He's pitched tremendous," Macha said. "When the season's over he's not going to have a zero ERA, but he's been throwing strikes."
Monday's makeup game could be a rematch of Friday's starters, given neither Milwaukee's Yovani Gallardo nor St. Louis' Kyle Lohse threw many pitches, but probably won't be due to strategic reasons.
Cardinals manager Tony La Russa is likely to go with Joel Pineiro on regular rest and save Lohse, a 15-game winner last year, for Tuesday to start a three-game series against the Chicago Cubs. Macha could keep Braden Looper on regular rest in the makeup game and save Gallardo for Tuesday at Houston given the right-hander threw his first career complete game against the Astros on April 24.
Five of the first eight hitters reached safely against Gallardo, with Rasmus' shot putting the Cardinals ahead 2-0 in the second. Play was halted after eighth-place hitter Joe Thurston walked with one out in the second.
The homer would have been the second in two games and third overall for Rasmus, a rookie getting more playing time due to injuries to fellow outfielders Rick Ankiel and Ryan Ludwick.
"It ain't going to count," Rasmus said. "So it don't matter."
Gallardo was happy to have his outing washed away after 30 pitches. Blustery conditions preceding the rainstorm had unnerved him during his abbreviated outing.
"You're up on the mound and the wind's almost blowing you off the mound," Gallardo said. "After every pitch I kept looking up and it seemed like it kept getting harder after each pitch, so I knew it was just a matter of time."
Lohse allowed one hit in two innings while trying to put the weather out of his mind.
"It looked pretty bad," Lohse said. "But I don't think about that stuff before my start. I did what I was supposed to do."
The Brewers and Cardinals, both 21-14, entered their first series of the season tied for the NL Central lead. The Central has been a surprise success story, with the Cubs and Reds at 20-14 Friday.
"I don't think back when you started the season a lot of people in baseball thought there would be four teams doing what they're doing in this division," Macha said. "That's why we're holding the season."