LOS ANGELES -- In Jordan Montgomery’s final month with the Yankees -- one that undoubtedly played a role in him being dealt to the Cardinals on Aug. 2 -- he struggled through a six-start stretch during which he was 0-2 with a disappointing 4.91 ERA.

Following the trade, Montgomery seemed like a different pitcher, one who aggressively pitched inside more, kept the ball in the park and looked like a potential staff ace. In his first five weeks as a Cardinal, Montgomery went 5-0 over a seven-start stretch -- all seven of them being Cardinals wins -- while compiling a sparkling 1.45 ERA.

Now, following a third consecutive rocky outing -- another one in which Montgomery was hurt badly by long balls -- the Cardinals and the highly competitive, 6-foot-6 left-hander are trying to figure out where and how things changed so dramatically for him.

“Sadly, I thought that was some of the best stuff I’ve had all year and I just got barreled up every time,” Montgomery said after the Cardinals fell behind early and lost 6-2 to the hard-hitting Dodgers. “It’s hard trying to get outs [against the Dodgers]. I think I got barreled up, even on outs. It doesn’t always go the way you want it to. I’m a competitor and I hate losing, but baseball stinks sometimes.”

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What especially stinks for Montgomery is the fact that he’s given up 13 earned runs, 21 hits and five home runs in the last three starts -- numbers that run completely counter to the success he had immediately after being traded from the Yankees to the Cardinals. In his first seven starts with the birds on the bat across his chest, Montgomery yielded just seven earned runs and 31 hits -- a stretch that included a win over the Yankees, a strong performance against the NL Central-rival Brewers and a one-hit shutout of the Cubs at Wrigley Field.

As much as he’d like to be ramping up for the playoffs, Montgomery said he will spend the next few days doing a deep dive on his pitching patterns and trying to uncover what all has gone wrong for him down the stretch.

“I’m going to want to be back out there tomorrow because I’m going to be sick about this for about three days,” said Montgomery, who saw his record fall to 5-3 and his ERA rise to 3.12 with St. Louis. “I’ve just got to put my nose to the [grindstone], go back to work and be ready to get back out there.”

On Saturday, Montgomery was shocked -- not that a Dodgers squad with a plus-315 run differential touched him up for six runs and seven hits -- but by the manner in which they did so. Will Smith hit a hanging curveball -- “My worst pitch of the night,” Montgomery said -- 417 feet and 104.4 mph off the bat, per Statcast. Trayce Thompson took it another level by drilling a Montgomery fastball 438 feet and 108.1 mph, while rookie Miguel Vargas hit his first MLB home run 390 feet in just his 12th big league game.

“I’m using a lot of the zone,” said Montgomery, who gave up 15 home runs early in the season with the Yankees. “I’m going up and in and down and away and I’m changing speeds. Watching film can only get you so much. So, I just have to stick with it. I don’t think I was tipping [pitches]; they were just making good swings.”

Cardinals manager Oliver Marmol sided with his left-hander, feeling Montgomery’s stuff was sharp, but the Dodgers were on his pitches and barreled nearly 10 pitches over four innings.

“Overall, I thought his stuff was pretty good, but they just beat him,” Marmol said. “He had a good approach overall and he was good stuff-wise. His location was no different than other outings and his velo popped, but they got to a couple of his pitches. … These guys hit homers, and today they got to him for a couple, but I actually liked his stuff.”

With fewer off-days in the postseason this year, Marmol said he wants five starting pitchers ready to go come playoff time. With Jack Flaherty, Jose Quintana and Dakota Hudson pitching well behind frontline starters Adam Wainwright and Miles Mikolas, Montgomery could be pitching for a spot in the rotation, as odd as that sounds, following his nearly flawless early tenure with the Cards.

“I’m trying to finish the season strong,” he said adamantly. “It’s easy to be like, ‘Oh, I’ve got two more starts and then I can start thinking about the playoffs,’ and then you get your butt kicked like I did today. So, I’m trying to put blinders on for this last start and then go from there.”