Angels’ Jered Weaver continues to struggle as Giants get to him early

Mike Scioscia went with an unorthodox lineup Sunday, batting pitcher Jered Weaver eighth and struggling catcher Chris Iannetta ninth against the San Francisco Giants, a move that seemed to buoy the 6-foot-7 right-hander.

“He’s pumped,” the Angels manager said when asked how Weaver felt about hitting eighth. “He’s walking a little taller.”

Not for long. The Giants ambushed Weaver in AT&T Park, belting three of his first eight pitches for two home runs and a triple en route to a 5-0 victory that completed a three-game sweep and dropped the Angels seven games behind the upstart Houston Astros in the American League West.

The loss also raised serious concerns about the Angels’ erstwhile ace, who was tagged for five runs and 10 hits in five innings, striking out two and walking one to fall to 0-4 with a 6.29 earned-run average. For the first time in 10 years, Weaver has opened a season with six winless starts.

Weaver won 49 games from 2012-2014 with a diminished fastball, but his velocity has dropped even more this season, to 83-85-mph, and he has not had consistent command of his curve and changeup. That has left him with little margin for error, and hitters are teeing off on him to the tune of a .308 average and eight homers.

“I’m pretty much serving [batting practice] up there now,” a frustrated Weaver said. “I have to work with what I’ve got. … I’m not hurt. Everything feels good. It feels like it’s coming out a lot better than it is. It’s weird, man. I don’t know. I’ve got no answers.”

Neither does Scioscia, who is not at a point where he would consider skipping Weaver in the rotation or moving him to the bullpen.

“I don’t think there’s any magic pixie dust you can sprinkle on it and get him going right now,” Scioscia said. “It’s going to be a process. It’s a matter of trying to be consistent with what he has. When he’s on, he can mix and match and keep guys off balance.”

Neither Giants leadoff man Nori Aoki nor No. 2 batter Joe Panik had homered before Sunday. Aoki drove Weaver’s first pitch of the game over the wall in right field, and Panik hit his fourth pitch over the same wall for a 2-0 lead.

It was only the third time in franchise history the Angels gave up back-to-back homers to start a game. Weaver was on the mound the last time it happened, against Seattle (Ichiro Suzuki, Chris Snelling) on Aug. 29, 2006.

The third batter, Angel Pagan, missed another homer by a few feet, crushing Weaver’s eighth pitch for a triple off the right-center-field wall.

Weaver said he told Iannetta in a pregame meeting that he knew Aoki would swing at the first pitch, “so I tried to get him off-guard with a fastball in, and it was up, middle in,” Weaver said. “That’s not the way you want to start a game, for sure.”

Weaver stranded Pagan at third, getting Buster Posey and Brandon Belt to ground out and striking out Brandon Crawford, raising hope for the Angels that he might rebound as he did Tuesday in Oakland, when he gave up five runs in the first and retired 15 of the next 16 batters.

But the Giants added a run in the third on Belt’s fielder’s-choice grounder, and two in the fifth when Posey singled with two outs, Belt hit a ground-rule double and Crawford hit a two-run double for a 5-0 lead.

“He’s throwing not much different than last year,” Iannetta said. “His stuff is good. He’s making a few mistakes over the middle of the plate. This little funk he’s in, whatever it is, I’m sure it will pass.”

Weaver got no support from an offense that managed three hits, was shut out for the second time this season and held to three runs or fewer for the 15th time in 25 games. And waiting for the Angels in Anaheim on Monday night will be Seattle ace Felix Hernandez, who is 4-0 with a 0.88 ERA in his last six starts against them.

“Everything is magnified at the beginning of the year — this is a stretch where we haven’t hit to our capability,” Iannetta said. “I don’t think it’s going to last all year — that would be impressive. I think it’s going to turn around. We’ll get in a groove, catch fire and start swinging it better.”

mike.digiovanna@latimes.com

Twitter: @MikeDiGiovanna