Resurgent Chris Iannetta has helped power Angels’ playoff push

Pitcher Dan Haren would “take a catcher who hits .100 if I can get into a good rhythm with him,” though his general manager and Angels fans who grew tired of Jeff Mathis’ weak at-bats would disagree.

Jerry Dipoto’s first move as GM was to upgrade offensively behind the plate, acquiring catcher Chris Iannetta from Colorado for pitcher Tyler Chatwood last Nov. 30. Iannetta had a career .357 on-base percentage and averaged 14 home runs a year from 2008 to 2011.

Three days later, Dipoto shipped Mathis and his career .194 average and 26 homers — total — in 51/2 seasons to Toronto for pitcher Brad Mills.

Five months into a season interrupted for almost three months by wrist and forearm injuries, Iannetta is finally rewarding Dipoto with an offensive surge that has helped the Angels push for a playoff spot.

Batting ninth, Iannetta has hit .390 (23 for 59) with three homers and 12 runs batted in over his last 18 games, raising his average from .194 on Aug. 13 to .268 entering Friday night’s game against Detroit. With 22 walks in 181 plate appearances, he has a .359 OBP this season.

The bottom-of-the-order punch has added another dimension to an already productive lineup and helped the Angels win 12 of 15 games to move to within 21/2 games of a wild-card spot.

“It makes it very difficult,” Haren said of the impact a No. 9 hitter like Iannetta has on an opposing pitcher. “When a guy at the bottom of the order is swinging like Chris, it turns the lineup over, and the starter has to face the middle of the lineup three, maybe four times.

“It’s hard enough to get the middle out once, let alone that fourth time, especially against teams like the Tigers with Prince Fielder and Miguel Cabrera.”

Iannetta, 29, keeps meticulous notes on every Angels pitcher and is constantly asking them how he can improve defensively. At the plate, he’s not as cerebral.

“I’m just having fun,” Iannetta said of his hot streak. “I’m not going to overanalyze it. I don’t even want to analyze it. I’m not really focused on hitting. I’m focused on defense.”

That’s music to the ears of Manager Mike Scioscia, the former Dodgers catcher who has emphasized defense over offense at the position.

“In the batter’s box, Chris has found a comfort zone — he’s set the table for some important guys,” Scioscia said. “But more important to us, defensively, he’s getting comfortable and more mentally in tune with these guys.”

It’s been a bit of a crash course. While catching Jered Weaver’s no-hitter against Minnesota on May 2, Iannetta was hit by a pitch on the right wrist. Nine days later, he had surgery to remove a broken bone.

During a minor league rehabilitation stint in early June, Iannetta suffered a forearm strain that set him back six more weeks. He finally returned on July 29 but looked a little lost at and behind the plate.

“It was a matter of catching up to the speed of the game,” Iannetta said. “Even though I’ve done this for a while, when you take that much time off, you need some reps to slow the game down.

“If you add stress to the equation, everything speeds up. The pitchers throw harder than they are, the ball moves more than it does, and your reaction time slows down. Everything is tougher.”

Iannetta batted .188 (6 for 32) in his first 12 games back, but that didn’t disturb him as much as some costly passed balls and miscommunication with pitchers.

His most glaring mistake came Aug. 17, when he flashed the wrong sign on a pitch that a confused Jered Weaver lobbed to the backstop.

Weaver was rocked for nine runs in a 12-3 loss, saying afterward he and Iannetta “just couldn’t get on the same page.” Relations have improved since — the rotation is 10-2 with a 3.19 earned run average in the last 15 games after going 3-7 with a 6.49 ERA in 18 games from Aug. 1 to 19.

“I took that extremely personal,” Iannetta said of the Weaver mix-up. “I’m here to help and assist, not to be a detriment to the team. I beat myself up over that for a very long time. But we picked each other up and got past it the best we can.”

mike.digiovanna@latimes.com

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