MILWAUKEE -- With the Brewers weathering several injuries on their starting pitching depth chart in the early going this season, Corbin Burnes is that much more important to their rotation and overall success.

Monday, however, was not the Milwaukee ace and 2021 National League Cy Young Award winner’s night. Burnes gave up seven hits -- including four home runs -- and five runs in five innings vs. the Astros, as the Brewers dropped the series opener 12-2 at American Family Field.

It’s the first time Burnes has allowed four homers in a game in his career. The last time he surrendered three was in 2019, when it happened four times.

“For the most part, outside of the four home runs, we threw the ball well,” Burnes said. “We were getting weak contact and got some punchouts. ... We made mistakes to good hitters, and good hitters hit the ball out of the ballpark.”

Burnes walked a pair of Astros in the first inning -- the tough lefty tandem of Yordan Alvarez and Kyle Tucker -- but got through the inning unscathed. In the second, he left a 95-mph sinker thigh-high to Corey Julks, who crushed it 401 feet over the left-field wall. 

Julks’ solo shot had an 108.2 mph exit velocity. Martín Maldonado followed with a solo homer two batters later, driving a 94 mph cutter from Burnes 411 feet to left field.

Mauricio Dubón led off the fifth inning with a solo homer off Burnes, on an 86 mph slider middle-down. Alvarez came up moments later and hit a two-run homer on a 93 mph cutter from Burnes, driving it 425 feet with an 110 mph exit velocity.

“Every mistake that I made tonight got hit hard,” Burnes said.

Elvis Peguero took over for Burnes in the sixth and allowed four straight batters to reach base with one out. Hoby Milner came on to face Alvarez, and the big lefty hit a grand slam that broke the game open.

“It’s a good lineup. They’re a hot team right now,” said Burnes of the Astros, who have won eight straight games. “They’re playing well. They came out, swung the bat, pitched well, played good defense. They beat the crap out of us.”

Burnes has now made 10 starts this season, and after an up-and-down first few rotation turns (4.55 ERA through five outings), he threw four consecutive quality starts entering Monday.

“I would say he hasn't put together a long string of good starts. I thought the two previous starts were pretty darn good,” manager Craig Counsell said when asked of Burnes’ season so far. “Probably just spraying the ball a little more than we've seen. The stuff is, by the way we look at it, really the same. Some misses, maybe a little bigger than usual. But nothing that's like not really close to like putting himself right on track.”

And that’s important for the Brewers with their banged-up pitching staff. Before Monday’s loss, Eric Lauer landed on the 15-day injured list with an impingement in his right shoulder.

Wade Miley went on the 15-day IL last week, and Brandon Woodruff is on the 60-day IL. Aaron Ashby underwent shoulder surgery in April and is on the 60-day IL. Adrian Houser opened the season on the IL and only made his season debut earlier this month. Freddy Peralta and Burnes remain from the Opening Day rotation.

Counsell stressed it’s not on Burnes – or any one guy – to hold up an entire staff as it goes through this trying stretch.

“It's not all on Corbin,” Counsell said. “He's got his job to do every fifth day, like every starter has to do. It’s not on one guy. None of this is on one guy. It's on [playing well daily, [playing] well consistently. And Corbin is part of that, certainly. But it's not on Corbin.”

“I can go out and throw once every five days,” Burnes said. “The other guys can go out and throw once every five days. We’ve got to do what we can do when our name is called to go out there. I haven’t done my job for the most part this year, so I could definitely be better.”