ANAHEIM, Calif. -- Last year at this time, the Oakland Athletics' Sonny Gray and the Los Angeles Angels' Hector Santiago were performing at an All-Star level. Now, both find themselves struggling mightily, and each seeks to reverse course at the other's expense when their respective teams meet Sunday at Angel Stadium.

Gray made the American League's All-Star team in just his second full season before finishing 14-7 with a 2.73 ERA, good for third place in the league's rankings. The right-hander also led the league with two shutouts and finished third in voting for the Cy Young Award.

This year, however, Gray is trying to end a five-game losing streak that began before a strained right trapezius muscle put him on the disabled list. During that losing streak, a career worst, Gray has compiled a 6.41 ERA. For the season, Gray leads the majors with 11 wild pitches.

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But in his last start Tuesday night against the Milwaukee Brewers, Gray conceded only one earned run and one walk in six innings while scattering seven hits and collecting seven strikeouts for his first quality start since April 22, the date of his last victory.

A's manager Bob Melvin believes Gray has turned a corner since returning from the disabled list June 5.

"Every start he's had since he's come back, less really one inning, has been really good," Melvin said. "His stuff's been there. Everything has been really crisp. Everybody goes through a period of struggle at some point in their career. Since he's been back, he's much more like the old Sonny Gray we're used to seeing."

Meanwhile, Santiago struggles to find the consistency that enabled him to compile a 2.33 ERA at the All-Star break and join Gray at the All-Star Game. This season, the left-hander saw his ERA swell to 5.64 before he threw quality starts in his last two appearances.

"Hector's been hot and cold," Angels manager Mike Scioscia said. "He's thrown some games where you just go, 'Wow!' Everything's working for him; the velocity's there and he's got his command. Then there are some games where he came out not having the stuff you just saw the start before.

"But the last couple of starts, you're seeing what we saw earlier in the season. He's throwing fewer pitches behind in the count. He's getting into the strike zone early with good stuff and letting all his pitches play off of each other."

The Angels' and Athletics' pitching staffs have more in common than two struggling former All-Stars. Three of Los Angeles' projected starters are on the 60-day disabled list. Oakland, meanwhile, has two on the 15-day disabled list, two on the 60-day disabled list and two out for the season after undergoing Tommy John surgery earlier this year.