BALTIMORE -- A’s manager Mark Kotsay said one key to Adam Oller’s ability to go long in his last start was pitch execution.

Kotsay said Oller was “able to control the strike zone and get some length” in his eight shutout innings against New York on Aug. 27.

But Saturday night, the Athletics’ right-handed starter was not able to repeat that feat in an 8-1 loss to the Orioles, Oakland’s fourth in a row and 85th overall. Oller fell to 2-7.

The game boiled down to Oller’s inability to keep his fastball in the strike zone -- falling behind hitters and surrendering a career-high four home runs, two by Ryan Mountcastle -- that helped the Orioles build an early lead.

"I didn't have any fastball command tonight and it was pretty prevalent with the walks,” Oller said. “[I was] falling behind in counts quite often.”

Oller walked the first batter he faced -- Cedric Mullins -- and in the third, Anthony Santander. Both came around to score in front of mammoth swings from Mountcastle.

"The first one we were trying to go down and in, and it leaked right over the plate,” Oller said about facing Mountcastle. “It was down and in but it was too close to [the] middle. The next one we were trying to go down and away and missed middle with it and I paid for both of those.”

A pair of two-run shots -- one to left field and the other to right field from the Orioles first baseman -- put Oakland in an early deficit. Oller was unable to find the rhythm he had in his last start against the first-place Yankees, or against the Marlins on Aug. 22, when he allowed three runs over six innings in a 3-0 loss.

"That just wasn't the same guy from his previous two starts,” Kotsay said. “This is part of that process I think with these young pitchers. It is a learning curve for them. I think tonight he left a lot of pitches in the middle, got hurt, couldn't command really any of his pitches and was forced to just kind of throw a strike. At this level, against this type of team, with these hitters, you are going to pay the price when that happens."

According to Baseball Savant, Oller’s fastball did not have the same spin rate (64 points off his season average). He said the rest of his repertoire was affected when he could not stay in the strike zone with the four-seamer.

"A lot of it is based off of fastball command because everything else that I'm throwing is off of that, especially [my] cutter,” Oller said. “I'm trying to tunnel that off of the fastball.

“The same thing with [the] changeup and breaking ball for that matter. When you are trying to go up with a fastball to set up a breaking ball down and you're sailing the ball, it's a pretty easy take on the next breaking ball as well."

Oller allowed six runs on eight hits with three walks and four strikeouts over five innings, throwing only 56 strikes over 95 pitches. Baltimore managed six extra-base hits versus Oller, with Mullins and Santander also cranking solo shots.

The A’s have now been held to one run or fewer 42 times, the most in the Majors this season. The Tigers are next, having been held to one run or fewer 37 times.

Trailing 4-1 in the fourth, the A’s had a promising opportunity to put runs on the board, loading the bases on consecutive singles by Shea Langeliers, Dermis Garcia and Cody Thomas against Orioles starter Austin Voth. Nick Allen then lined a shot to right field that was caught by Kyle Stowers.

The Orioles went to southpaw Keegan Akin, so Kotsay countered with pinch-hitter Chad Pinder. But Pinder could not put a good swing on an Akin fastball and grounded into a deflating inning-ending, 6-4-3 double play.

"That inning there we had some momentum,” Kotsay said. “[If] Nick's ball falls in there -- it was a hard line drive -- but [the] right fielder made a nice play on it. The left-hander they brought in I felt we had a great matchup with Chad and unfortunately, he just got on top of a fastball and ended up rolling into a double play. They killed our inning and our rally, and really after that we didn't gain much more momentum."