SEATTLE (AP) — Sick of the mistakes, the effort and the inability to string together victories, Lloyd McClendon will have a new approach and message for the Seattle Mariners when the second-half of the season begins.

It might be the only way to salvage a season that so far is one of the biggest disappointments in baseball.

"I've given my club a lot of string and allowed them to do a lot of things but it's not working," McClendon said. "We're going to change things."

The Mariners committed three errors in one of their sloppiest performances of the season on Sunday in a 10-3 loss to the Los Angeles Angels. Seattle dropped seven games below .500 and 7 ½ games back of the Angels in the American League West standings, having alternated wins and losses in its last 12 games.

It was not the kind of effort to inspire optimism that a second-half run was on the horizon for a team many expected to be contending for the division.

"It was a very bad performance. In a lot of ways it was very embarrassing and we are much better than that," McClendon said.

Chris Iannetta hit a two-run home run and David Freese added a two-run double as part of a six-run sixth inning, and the Angels entered the All-Star break in first place in the AL West. The Angels won for the 11th time in 14 games and leaped past Houston into the AL West lead for the first time since April 17 after the Astros lost their sixth straight on Sunday.

Seattle starter Taijuan Walker (7-7) was knocked around for six earned runs in his worst outing in two months. Freese just missed a homer, doubling off the top of the wall to end Walker's day in the sixth. Iannetta followed with his fifth homer of the season off reliever David Rollins to blow the game open.

The mistakes by Seattle's defense didn't help, although Walker was partly at fault. The Angels took a 2-0 lead helped by Robinson Cano's fielding error that allowed Erick Aybar to score and Walker's wild pitch that sent Freese home. A throwing error on left fielder Mark Trumbo allowed Mike Trout to score with two outs in the third inning. Trout later scored in the sixth on a throwing error by Walker that ignited the six-run inning for the Angels.

"It was one of those days when I felt like I had pretty good stuff and was working pretty well," Walker said. "Just had that throw there in the sixth and it went downhill from there."

The defensive miscues were combined with another day where the Mariners offensive was silent. Angels' starter Andrew Heaney (3-0) pitched seven shutout innings, giving up just five hits. He struck out six and walked only one, retiring 11 of the final 13 batters faced.

Seattle had runners at second and third in the second inning but Heaney struck out Logan Morrison and Mike Zunino to end the threat. In the fifth, Brad Miller and Austin Jackson put together consecutive two out hits but Cano struck out swinging wildly at a 3-2 slider out of the strike zone.

"I felt like throughout the day when I really needed a punch-out or needed to make a good pitch, I felt like I could do it," Heaney said.

Seattle scored twice in the eighth on RBIs from Dustin Ackley and Kyle Seager, and Seth Smith hit a pinch-hit solo homer leading off the ninth.

ROSTER MOVE

Seattle reliever Danny Farquhar was optioned to Triple-A Tacoma after the game. There was no corresponding move.

NEW ADDITION

Angels' pitcher Hector Santiago was added to the American League All-Star Game roster after Oakland's Sonny Gray pitched on Sunday. It's the first All-Star Game selection for Santiago.

FIRST PITCH

U.S. women's national team midfielder Megan Rapinoe threw out the first pitch before the game. Rapinoe, who played for the Seattle Reign FC in the NWSL, was given a standing ovation and threw from the top of the pitching mound with a full windup.

UP NEXT

Angels: The Angels will open up after the All-Star break with a 10-game homestand starting against Boston.

Mariners: Seattle will next play on Friday in New York against the Yankees, part of a seven-game road trip.