The A’s entered the 2020 campaign with visions of Frankie Montas leading the way for a deep playoff run as anchor of the rotation. With the postseason now just a week away, the right-hander’s recent scuffles might force the club to leave him out of their Wild Card Series rotation plans completely.

A rough stretch that began last month continues to snowball for Montas, who struggled in Tuesday’s 7-2 loss to the Dodgers at Dodger Stadium. Lasting just four innings and tagged for five runs, including a season-high three home runs surrendered, Montas has now allowed at least four earned runs in all but one of his past six outings.

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“He’s not throwing the ball as consistently where he wants to with all his pitches like he was early in the season,” A’s manager Bob Melvin said of Montas. “[The Dodgers] got him on the run early and this is a pretty good team. When you make mistakes, they make you pay. They’re pretty good about laying off pitches and making you throw it over the plate.”

Dating back to his start on Aug. 18, which came on nine days of rest following back tightness, Montas now holds a 10.88 ERA in six starts over that span, which ranks as the highest among Major League starters with at least 20 innings pitched in that time.

Neither Melvin nor Montas has used the back issue as an excuse, and it doesn’t appear to be affecting his stuff, as Montas’ fastball velocity maxed out at 98.1 mph on Tuesday. But something appears to be off, especially when you take into account his dominance earlier in the season.

“I feel great. My body and arm feels good. I’m just going through a tough time right now and trying to get out of it,” Montas said. “Today was tough. I feel like I was throwing strikes and everything I was throwing was getting hit. One of those tough days.”

Through his first four starts, Montas posted a 1.57 ERA. His impressive stretch included his first career American League Player of the Week Award for the week of Aug. 3-10. One clear difference is the home runs. In those first four outings, Montas did not allow a home run in 23 innings. But in his current troubling six-game stretch, Montas has allowed 10 home runs in 24 innings.

Part of the struggles could be stemming from a lack of command with his splitter, the pitch Montas added to his repertoire in the spring of 2019, which later helped him to a superb 2.63 ERA over 16 starts last season. Of his 70 pitches on Tuesday, Montas threw the splitter just 12 times, the least of his four types of pitches.

Though his sinker comes in at a blazing 98 mph, the lack of a splitter leaves little variation in pitch speeds and becomes a bit more predictable for opposing hitters, especially when it is left over the heart of the zone like it was on his two solo homers allowed in the fourth. Montas also gave up a two-run blast to Max Muncy in the third on a slider that caught far too much of the lower half of the zone.

“He’s just not quite there with his mechanics,” Melvin said. “Right now, his split is not as good as it was before, and he’s centering some sliders. It’s not a matter of stuff right now. It’s probably a little bit of confidence that he can’t get on a roll.”

Departing Tuesday’s game with the A’s trailing 5-2 after four frames, Montas will likely get one more shot at that much-needed confidence boost with a start before the regular season wraps up over the weekend. But at this point, Montas is likely on the outside looking in when it comes to starting a game in the opening round of the playoffs.

As for the club as an entire unit, the A’s view this three-game series against the Dodgers as a barometer for how they might hang against a team they could theoretically face later this year in the World Series. They’ll have to do a better job on offense, which, outside of Robbie Grossman’s solo shot in the first, went cold in Tuesday’s loss. The A’s were limited to two runs over five innings against Dodgers starter Dustin May and shut out by the Los Angeles bullpen.

“That was the first time I’ve ever faced [May]. I’m looking forward to facing him again at some point,” Grossman said. “This is a great measuring stick. It’s not about what we do right now, but what we do in the first game of the playoffs and how we start that run.”