Blanton is a well-below-average Joe in Angels’ 10-5 loss to Boston

BOSTON — Another shoddy performance in Sunday’s 10-5 loss to the Boston Red Sox in Fenway Park dropped Angels right-hander Joe Blanton to 1-10 with a 5.87 earned-run average, worst among American League starters.

Blanton was rocked for seven runs — six earned — and eight hits, including prodigious home runs by David Ortiz, Jarrod Saltalamacchia and Mike Carp, in five innings and has now given up a major league-high 111 hits, 13 of them home runs, this season.

“This is probably the worst start to a season that I’ve had,” Blanton said.

Probably? It’s hard to imagine anything worse, and if Blanton doesn’t turn things around immediately, things could get historically bad.

Only one pitcher since 1980 has lost 20 games, Detroit left-hander Mike Maroth, who was 9-21 with a 5.73 ERA in 2003. Blanton is halfway there in only 13 starts. If he remains in the rotation and makes the 33 to 35 starts most pitchers make, he’ll have plenty of time to lose 20 games. Maybe even 25.

“Joe understands it’s a proving ground every day you’re in the major leagues,” Manager Mike Scioscia said. “He doesn’t have his head buried in the sand. He works very hard at keeping himself in shape, trying to be the consistent pitcher we know is in there. I think there is a sense of urgency to what he wants to do.”

It’s hard to tell sometimes. After his only win, on May 23 at Kansas City, Blanton, a nine-year veteran who signed a two-year, $15-million deal in December, seemed oblivious to the possibility of being demoted to the bullpen if he didn’t turn his season around.

“I’ve been doing this for a long time,” he said. “Why should I feel urgency now?”

Asked later if his next start would be a crucial one, Blanton said, “I don’t have anything to prove.”

If Blanton is to be believed, he made only one mistake Sunday, a changeup that Ortiz smashed for a three-run homer to right-center to cap a four-run third.

“If I could take back one pitch, it’s the changeup to Ortiz,” Blanton said after the Angels lost for the seventh time in nine games. “I was trying to make it sink down and away. I pulled it middle-in and up. I made one mistake and it cost me three runs. That changed the complexion of the game.”

So what about the pitches that Saltalamacchia and Carp crushed for solo home runs — estimated at 427 and 422 feet, respectively — to straightaway center to open the sixth?

“They were inches from where I wanted them, a get-me-over curve to Carp and a fastball to Saltalamacchia that was maybe more third-in instead of on the corner. Definitely not a bad pitch.”

Blanton also said he feels as though he’s “thrown the ball like I want to” since his first three starts, when he was 0-3 with an 8.59 ERA. But in 10 starts since, he has a 5.22 ERA, not exactly Cy Young Award-caliber stuff.

Judging by comments on social media, fans seem as irked by Blanton’s perceived ambivalence as his poor results. And the pitcher probably fueled those sentiments when asked if it was tough to see a 1-10 record attached to his name.

“There’s nothing I can do about it,” Blanton said. “I’m never frustrated. It is what it is. I went out and did my best today. That’s all you can do.”

mike.digiovanna@latimes.com

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