OAKLAND -- With lefty Andrew Heaney at 94 pitches through five innings, Angels manager Joe Maddon opted to leave him in to face the left-handed hitting Matt Olson to lead off the sixth with the game tied.

But Heaney gave up a single on a 1-2 curveball to Olson and was immediately pulled for right-hander Steve Cishek, who had posted a 1.65 ERA over his last 17 games, dating back to May 10. But Cishek struggled, allowing three runs to score in the inning, including one charged to Heaney, sending the Angels to a 6-4 loss and a series defeat on Tuesday. It halted the club’s momentum, as the Angels had headed into Oakland on a six-game winning streak.

“It was a nice setup for Shek,” Maddon said. “It's just something I had set up before the game. Andrew was at around 100 pitches and would've really had to work to get through that part of the batting order. I just thought it was the right time to bring Shek in the game."

Cishek simply couldn’t find the strike zone, as he walked the first two batters he faced before giving up the go-ahead run on a sacrifice fly to Seth Brown on a 2-1 sinker over the heart of the plate. He then fell behind Elvis Andrus with a 2-0 count and gave up a two-run double into the left-center-field gap on a fastball just below the zone.

"The command was not there,” Maddon said. “He's been outstanding. I could not have felt better about him in that moment with that part of the order coming up. We had it planned out before the game, but it didn't work out.”

The three-run deficit was too much for the Angels to overcome, though two-way sensation Shohei Ohtani did crush a solo shot in the eighth off a 98 mph fastball from lefty Jesús Luzardo for his 18th blast of the year. It had an exit velocity of 115.8 mph and sailed an estimated 429 feet into the right-field bleachers.

Cishek’s outing also spoiled an otherwise solid start from Heaney, whose biggest issue was efficiency. He made it through five-plus innings, allowing three runs on five hits and a walk with six strikeouts to fall to 4-4 with a 4.45 ERA in 12 starts this year.

Heaney, who had been leaning heavily on his fastball over his last two outings with great success, threw his fastball often early but mixed in more changeups and curveballs as the game went along. He threw his four-seamer 57 percent of the time -- which is right around his season average -- and much lower than the 75 percent of the time against Kansas City and 73 percent of the time against San Francisco.

Heaney said throwing fewer fastballs wasn’t part of the game plan but something that evolved as the game went along.

"I'm not calculating the amount of fastballs I'm throwing as the game is going,” Haney said. “Those things kind of end up being what they are at the end of the game. I'm trying to get guys out with what I think is working and what they are doing. It's punch-counterpunch and trying to react to what they are doing."

His lone rough inning came in the third, when he gave up a one-out RBI double to Mark Canha on a 1-2 fastball up in the zone and an RBI single to Matt Chapman on a 1-2 changeup several inches below the zone. Heaney said it’s easy to overanalyze pitch selection and didn’t believe he was hit hard -- but suggested that he needs to be more efficient next time out.

"I gave up a double on a fastball to Canha, gave up a single to [Tony] Kemp on a fastball,” Heaney said. “You can go back and look at it in different ways. I gave up a single on a good changeup to Chapman and he put a better swing on it. I threw a breaking ball, and I'll have to look at it, but it probably caught too much of the plate on a two-strike pitch to Olson. So you can look at pitch selection, and I probably could be better, but I don't think they were necessarily on a lot of my stuff. They just strung together a couple hits in that third inning and that was kind of the difference."

The difference between the Angels and the first-place A’s in the AL West is now eight games after the two losses, but Maddon said he still likes the way his club is playing.

“It's suboptimal, as they say,” Maddon said, "but we have a chance to get back to .500 tomorrow before we get back home. There's nothing to be upset about. The guys are playing hard and doing a lot of good things. We're banged up a little bit, so I give my guys a lot of credit."