Garrett Richards’ power dims in Angels’ 9-4 loss to Seattle

Mike Scioscia fell in love with Garrett Richards’ power arm in August, moving the rookie to the bullpen believing he could provide the kind of boost starter-turned-reliever Kelvim Escobar gave the Angels during their 2005 run to the American League championship series.

That love, at times, has gone unrequited.

In a span of four batters during the decisive seventh inning Thursday, Richards walked Trayvon Robinson with the bases loaded, gave up a run-scoring single to Kyle Seager, a sacrifice fly to Jesus Montero and an RBI double to John Jaso.

A one-run Seattle lead turned into a five-run bulge, and the Angels couldn’t recover. Their 9-4 loss to the Mariners snapped a five-game winning streak and prevented them from moving closer to a playoff spot.

A win would have moved the Angels to within one game of Oakland for the second wild-card spot. Instead, the Angels remain two games behind the Athletics with six to play. They’re also six games behind the AL West-leading Rangers entering a three-game series in Texas.

“We know what we’re up against,” said Dan Haren, who allowed three runs, two earned, and six hits in 51/3 innings. “Hopefully, we play well Friday and put a little pressure on Oakland. This loss hurts, but we have to shrug it off.”

An uncharacteristic error by shortstop Erick Aybar, who failed to catch first baseman Kendrys Morales’ throw on Dustin Ackley’s fielder’s-choice grounder, led to an unearned run that gave Seattle a 3-2 lead in the fifth.

Haren struck out Montero with his 80th pitch to start the sixth but was pulled in favor of left-hander Nick Maronde, who got Jaso and Justin Smoak to fly out.

“Of course I had gas left in the tank, but I understand the situation. I’m not going to complain,” said Haren, who is 12-12 with a 4.32 earned-run average. “I wish my year had gone better, but they lost a little confidence in me going deeper in games. That’s more my fault.”

Maronde gave up a single to Michael Saunders to open the seventh and was pulled for Richards, who struck out the side in an inning against the Mariners on Tuesday night.

Brendan Ryan’s sacrifice bunt put runners on second and third, and Ackley was walked intentionally to load the bases. Four batters later, Seattle had a 7-2 lead.

“I’ve enjoyed this role and feel I can do it at this level,” Richards said. “You’re going to have your days when things go wrong. It’s up to me to make the adjustments, and today I got beat. You’re not going to be lights-out every game.”

Richards, with a 96-mph fastball and power sinker, has looked dominant at times. But in five of 18 relief appearances since Aug. 23, he’s allowed two or three runs, leaving the Angels open to second-guessing about whether he was thrust into a role for which he wasn’t ready.

But with Scott Downs and Jordan Walden hurt and LaTroy Hawkins and Jason Isringhausen ineffective, Scioscia had little choice.

“At times, he’s been terrific, and I think he’s done a good job under the circumstances,” Scioscia said. “He has a big arm, and there’s no doubt it’s something you can lean on in the middle of the game or late. But it didn’t work out this afternoon.”

mike.digiovanna@latimes.com

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