MILWAUKEE — For the third time in as many starts, Justin Steele’s outing ended on Saturday before he could throw a pitch in the fourth inning.

Not that he’s solely to blame for that. A few defensive miscues — including errors by Patrick Wisdom and Michael Hermosillo and Steele’s play on a roller up the line that could’ve gone down as an error, too — and an overturned double play call led to a 37-pitch first inning for Steele. By the time he got through the third he’d thrown 74 pitches, and manager David Ross made the choice not to send him back out for the bottom of the fourth in what was ultimately a 9-1 loss to the Brewers

“I thought he continued to try to make pitches,” Ross said about Steele’s first inning. “I don’t think things went his way after. I mean, I definitely think it’s frustrating when you’re out there and make pitches and plays don’t get made, but there’s going to be times he doesn’t make pitches and they make great plays behind him. I think that’s just baseball. So we’ve got to be a group that understands that we’ve got to pick up our teammates and try to have each other’s backs. We’re all going to make mistakes. You got to continue to execute pitches, and I think that’s his job and that’s all he can control.”

“It’s just baseball. You’re going to have them kinds of days,” Steele said. “Sometimes you’re lucky, sometimes they’re hitting line drives right at people and you go 1-2-3 with not a lot of pitches, and then you have cases like that. But like I said, it’s just baseball. You just got to grind through it.”

The overturned call might not have had much of an effect on Steele mentally — he said he didn’t have a problem refocusing after the challenge and review process — but physically, it cost him about 10 pitches (and after Rowdy Tellez’s base knock, another two runs). He was at 27 pitches when Lorenzo Cain grounded that ball to third base, and with the way the second and third innings went, there’s a chance Steele could’ve stretched his outing out further.

Instead, Steele’s night was done barely halfway to the minimum number of innings required to record a quality start and with him still not looking nearly as sharp as he did during his five-inning, zero-run performance on April 9.

However, that lack of length from the starting pitcher has become something of the norm for the Cubs through the first three-plus weeks of the season.

Through 21 games, starters have thrown at least five innings just seven times, at least six twice and at least seven only once. Manager David Ross made it clear from the get-go that starters weren’t stretched out enough to go deeper into games, but after an initial run of Kyle Hendricks, Steele, Marcus Stroman and Drew Smyly each going at least five innings the first turn through the rotation, the group as a whole has matched or exceeded that only three other times.

Overall, starters have covered 90 2/3 innings in 2022. Not far behind is the relief corps, which has covered 89 1/3 innings itself.

“I’d say everybody wants to take that next step forward,” Steele said of the rotation. “Start getting deeper into games, give the bullpen a little bit of a break, have them kind of games. It’s coming. It’s still early in the season. One month in.”

While that hasn’t drained the bullpen arms, the Cubs have had the luxury of being able to carry 15 arms into this series in Milwaukee. Once Monday comes along, though, that number begins to shrink.

May 2 is the date MLB and the MLBPA agreed would be the date that the 28-man roster would go down to 26. This past Tuesday, the sides agreed to allow teams to carry 14 pitchers on the active roster through May 30, but after that, teams will be down to 13.

An arm or two less in the bullpen doesn’t seem like a whole lot, but should there continue to be a lack of length coming from the rotation (starters have averaged just under 4 1/3 innings per outing), the bullpen will just continue to be leaned on until the starters get things turned around.

The shortened spring training was much better of an excuse for starters not pitching deeper into games at the beginning of the season. Now that the calendar is switching to May and a roster crunch is right around the corner, though, it’s no longer time to let pitchers stretch out like it’s an extended spring while the bullpen gets more and more early use.

There’s still no date set for Wade Miley and Alec Mills’ returns from the 10-day injured list, so that’s at least another turn or two through the rotation that’ll need to be addressed. Chicago does have the luxury of three days off in 11 days starting on Monday, and the Cubs are playing the option game by sending Mark Leiter Jr. to Triple-A Iowa, likely to keep him ready for when that 11 day stretch ends.

“I think it’s about just getting him stretched out,” Ross said. “… We’re going to need a starter at some point down the road. So getting him back to multiple innings is really all it is.”

The loss of an arm balances that out a bit, though, and with that, we may see more Chicago relievers throwing on back to back days to help cover innings. Rowan Wick (April 16-17), David Robertson (17-18) and Ethan Roberts (April 28-29) have each done it once. Meanwhile, Scott Effross has done it twice and has also pitched on six of the last 10 days.

Prior to this series in Milwaukee, the bullpen had done an exception job picking up the starters. Heading into Friday, the relievers had a combined 2.79 ERA over 80 2/3 innings with 94 strikeouts to just 27 walks. Over the last two games, however, the bullpen has combined to allow 10 earned runs, 11 hits and six homers in 8 2/3, showing how the relief corps could look when not at its best — and the loss of any bullpen arms on Monday won’t help.

There’s certainly different scenarios the Cubs will sort through before making final decisions on the roster come Monday. They’ll be down a pitcher, for sure, and if they decide to keep an extra bat on the active roster, they would be down two. Either way, that’ll add more strain on the relievers that remain on the big league club.

But if the rotation can find a way to eat more innings more consistently, that’ll go a long way toward alleviating some of that burden that’s been put on the bullpen throughout the first month of the season.