ARLINGTON, Texas -- The A's lost a starting pitcher and a left fielder Sunday, but they responded by bolstering their postseason hopes by completing a sweep of Texas with a 5-1 win in Rangers Ballpark.

When starting pitcher Jarrod Parker had to be scratched because of a stomach ailment, the A's turned to left-hander Tommy Milone, who worked five innings and got the victory in his first start for Oakland in almost three weeks. Also absent from the lineup was cleanup hitter Yoenis Cespedes, who is bothered by a sore right shoulder.

The three-game sweep of the Rangers puts Oakland on the brink of securing a second consecutive American League West title. The A's have a 6½-game lead over the Rangers with 13 games left on the Oakland schedule. The magic number is eight, meaning any number of A's wins and Rangers losses totaling eight gives the A.L. West title to Oakland.

Was this weekend sweep a statement by the 88-61 A's?

"Call it what you want," Josh Donaldson said. "We came in and we won the games."

Donaldson moved from the No. 2 spot in the lineup to cleanup and hit his 23rd homer of the season to help the A's take a 2-0 lead in the first inning. The Rangers never led in the series and Oakland has scored first in 16 of its past 20 games.

"I don't think we're going to get too comfortable after this," Donaldson said. "We just want to keep playing the way we've been playing and that gets us where we want to go."

Milone got the news he was starting about an hour before the first pitch. Parker was sick to his stomach. The Rangers got to Milone for a run in the first but could not dent the plate against him after that. He'd thrown just one inning in the past two weeks, but he had enough give the A's five innings before turning it over to the bullpen.

"I didn't have time to think about it," Milone said of the start. "I just had to get ready and pitch. I wanted to step up. And for us to come out of here with a sweep, that's obviously huge."

Parker was feeling better after the game and could pitch as early as Monday night in the beginning of a three-games series against the Los Angeles Angels at the Coliseum, according to manager Bob Melvin. Rookie Sonny Gray is still listed as the starter Monday night.

The bigger question is Cespedes. He'd had a streak of seven games with at least one RBI -- 12 RBIs total in that stretch -- but that ended Saturday when Cespedes went 0 for 4. He was in the lineup Sunday, but his shoulder was hurt during this road trip, and the A's weren't willing to risk further injury.

Cespedes will undergo an MRI on Monday in Oakland.

"It'll be tough if he can't play for a while, but it won't be a downer," said right fielder Josh Reddick, who hit one of the three Oakland homers Sunday, joining Donaldson and Chris Young.

"We have guys here who will step up," Donaldson said. "That's what we do."

They made believers of the Rangers.

  • Jed Lowrie came out of the game in the eighth inning. He said he felt some hamstring pain Saturday and it increased Sunday. "They felt there was no reason to risk a deeper injury," Lowrie said. He said he expects to play Monday.

  • Texas, which came into the month with a two-game lead in the West, has lost 12 of 15, including five of six to Oakland. "I'm disappointed," Rangers manager Ron Washington said. "I expected us to respond better. But they outpitched us. They certainly outhit us."

  • Four of the A's runs came on homers, two on solo blasts from Donaldson and Chris Young early and a two-run shot from Reddick. The homers were one measure of the A's dominance in this series. Oakland hit six homers, the Rangers none.

  • Left-handed pitcher Brett Anderson, who left Friday's game with back spasms, seems to be recovering. Melvin said Anderson could be ready to pitch out of the bullpen by the start of the homestand Monday.

  • Catcher John Jaso, who has been out since the end of July with concussion problems, is starting to feel better. There's still no timetable for his return. It's unlikely to be this year.

    MONDAY'S GAME
    L.A. Angels (C.J. Wilson 16-6)
    at A's (Sonny Gray 3-3),
    7:05 p.m. CSNCA

    A.L. west race
    W L GB
    A's 88 61 --
    Texas 81 67 6

    MAGIC NUMBER
    Combination of A's wins and Rangers losses needed for A's to clinch A.L. West.