ST. LOUIS -- Already extremely frustrated with how the last three-plus months have gone for both him and the Cardinals in an otherwise lost season, right-hander Miles Mikolas’ anger hit new levels on Saturday, when he felt another poor outing came about because of forces out of his control.

Following a 6-1 loss to the Phillies at Busch Stadium -- the fifth straight this season by St. Louis to Philadelphia and the second of the year for Mikolas -- the veteran right-hander took aim at a strike zone that paved the way for Kyle Schwarber’s line-drive three-run homer, which left the bat at 114.1 mph, per Statcast.

Schwarber’s 44th home run came in the fifth when the Phillies were leading, 2-1, and the outcome was still in doubt. However, not long after Schwarber’s blast, Mikolas retreated to the Cardinals’ video room to check on the location of two sliders that he thought were strikes. When those calls didn’t go Mikolas’ way, he had to come up in the zone, and Schwarber delivered.

“[Schwarber] doesn’t like the ball down, and I painted two sliders down in the zone and I got neither call,” Mikolas said as his voice wavered with emotion. “You can go back and watch them. The first one was on the steal [when Philadelphia’s Johan Rojas took second base] and I know it’s tough to call a pitch on a steal, but that’s in the zone. The other one that appears to be in the dirt also catches almost a full ball on the bottom of the zone. So, I don’t know what to say.”

Mikolas’ frustration-filled night was the latest in an 11-start stretch where he has gone 1-7 with a 6.23 ERA and 11 home runs allowed. An All-Star for a second time in 2022 and once 4-1 this season, Mikolas has gone 3-11 with a 5.51 ERA over his last 20 starts. Even though he leads all of baseball with 32 starts, the Cardinals have dropped 19 of those outings as Mikolas has worked to reshape many of his pitches and reevaluate his pitching patterns.

“I know he’s frustrated and it hasn’t gone the way he would have hoped or we would have hoped,” said Cardinals manager Oliver Marmol, who pulled Mikolas after six innings of eight-hit, five-run pitching. “When you start looking at Miles and his two-strike execution, it got a little better as the game went on, but that’s been a difference for him. Being over the plate too much once he gets in those pitcher-advantage counts … that ability to execute with two strikes hasn’t been nearly as good as he would like.”

Schwarber’s game-breaking home run came on a 2-2 pitch, and it proved to be the sixth two-strike homer allowed by Mikolas this season, which ranks in the middle of the pack among qualified pitchers. However, Mikolas is tied with Colorado’s Kyle Freeland for the highest batting average allowed (.227) with two strikes on hitters this season.

Another area of concern for Mikolas, who turned 35 years old on Aug. 23: Hitters have hit 47 points higher this season after his 75th pitch compared to his performance on the first 75 pitches. Coincidentally, Schwarber hit Mikolas’ 77th pitch of the night -- an elevated 91.2 mph sinker -- for the three-run homer. However, it was the sliders thrown earlier in the at-bat -- and especially the one on the previous pitch -- that Mikolas would have liked to have gotten for strike calls so that he didn’t have to elevate a pitch to the power-hitting Schwarber.

“I liked the shape on [my slider] and I had some good location on it, but those were tough calls and I know they can go either way,” said Mikolas, who saw his season ERA climb to 4.84. “... A couple of calls [didn’t] go your way and then a couple of slow rollers get through whatever shift we had on, and that’s your ballgame right there.”

On Friday, Cardinals president of baseball operations John Mozeliak affirmed that the club will be aggressive this offseason in trying to acquire three starting pitchers. That plan, of course, is dependent on the only two starters under contract for 2024, Steven Matz and Mikolas, having bounceback seasons. Matz’s season ended early because of a left lat strain, while Mikolas’ ERA is his worst since becoming a Cardinal in 2018, when he went 18-4 with a 2.83 ERA.

“This is a guy we’re going to have to count on,” Marmol said of Mikolas. “He’s got the aptitude for it, he works hard and he’s got the mentality. He knows he’s at a point where he’s got to make some changes to keep up. … There’s some room there this offseason for him to get after it.”