Hector Santiago’s struggles weigh on Angels after loss to Rangers

The Angels don’t need Hector Santiago to anchor the rotation; that’s the job of capable veterans Jered Weaver and C.J. Wilson. They just can’t afford for the left-hander to be an anchor in the rotation, a pitcher who weighs the staff down.

But that’s what the numbers suggest after Santiago gave up five runs and seven hits in six innings Friday night in a 5-2 loss to the Texas Rangers in Angel Stadium.

Weaver, Wilson, Garrett Richards and Tyler Skaggs have combined to go 10-4 with a 3.29 earned run average. Santiago is 0-5 with a 5.01 ERA, and the Angels have lost all six of his starts.

“An 0-5 start is definitely not what we expected, but who knows, maybe I can get on a roll and go 12-5,” Santiago said. “It can’t get much worse. It can only get better.”

It appeared Santiago would crack the win column Friday when he cruised through five scoreless innings in 72 pitches.

Then the Rangers, who ranked 29th in the major leagues with 14 home runs entering the game, dropped the hammer on Santiago. Shin-Soo Choo lined his first pitch of the sixth over the center-field wall, Prince Fielder reached on a two-out infield single and Alex Rios crushed a two-run homer to left-center.

The at-bat to Rios was especially frustrating for Santiago, who was kicking himself for throwing a 2-and-1 changeup on the homer. Santiago initially shook off catcher Hank Conger, then stepped off the rubber before Conger called for the pitch again.

In the span of five batters, the Rangers turned a 2-0 deficit into a 3-2 lead.

“I threw Rios four or five changeups today — maybe a slider would have been a better pitch there,” Santiago said. “I felt like it was. I stepped off, got back on, he called it again and I figured this must be the right pitch. It was a bad pitch that I left up.

“I don’t know that I need to make more adjustments, it’s just a matter of making a better pitch late in the game. One more shake-off, and it’s a big difference.”

Santiago allowed a single and a walk to open the seventh before being pulled. Both runners eventually scored, inflating Santiago’s ERA and helping the Rangers snap a four-game losing streak.

Santiago, 26, has a vast repertoire consisting of a 94-mph fastball, cut fastball, slider, changeup and screwball, and Manager Mike Scioscia believes Santiago will find success when he learns to put pitch sequences together more effectively.

“It’s a balance of keeping hitters honest by changing speeds, of pitching to both sides of the plate with his fastball, of knowing when to bring his cutter and slider into the game,” Scioscia said. “I think our catchers understand him better, and he’s pitched better as he’s gotten in tune with that.”

But sometimes having too weapons can leave a pitcher indecisive.

“I think the best mind-set for Hector,” Scioscia said, “is to go as hard as he can for as long as he can and get as many quick outs as he can and let everything else fall in place.”

Not much has fallen into place for Santiago, who battled through back stiffness during his first two starts and lost an April 21 game in Detroit in part because the Angels committed three errors on one first-inning play.

The Angels entered Friday’s game leading the American League in home runs and slugging percentage, but they have scored a total of 13 runs in Santiago’s six starts.

“I’ve definitely had some tough luck, but I’ve made mistakes too,” Santiago said. “Hopefully it will turn around.”

mike.digiovanna@latimes.com

Twitter: @MikeDiGiovanna