The surging Oakland Athletics have started to run away with the AL West.
Continuing their playoff push, though, could prove difficult against C.J. Wilson, who hasn't lost in over two months.
Oakland (88-61) returns home seeking a sixth consecutive victory after sweeping Texas over the weekend. Josh Donaldson, Chris Young and Josh Reddick all homered in Sunday's 5-1 victory as the A's moved 6 1/2 games ahead of the second-place Rangers with 13 to play.
"It's a good lead, but we can't pay too much attention to the standings right now," Donaldson, batting .450 with four homers, six doubles, 11 RBIs and 12 runs during an 11-game hitting streak, told MLB's official website. "We don't want to get too comfortable. We want to continue steadily getting better, as we have. Hopefully that takes us to where we want to go."
Oakland, which has hit .305 with 32 homers while outscoring opponents 123-65 during a 16-4 stretch, will try to stay hot against Wilson (16-6, 3.44 ERA). The two-time All-Star, enjoying a career-high eight-game winning streak, is 12-1 with a 3.02 ERA in his last 17 starts.
"Of all the things we've talked about this year that haven't worked out, C.J. is on the other side of that ledger," manager Mike Scioscia said of Wilson, who is on the verge of a career-best 17th victory. "He's having just a terrific season, pitching deep into games. He's going to be 200-plus innings again. Every stat you look at is terrific for him."
The left-hander is looking to win a fourth consecutive start after allowing four runs and four hits in seven innings Wednesday in a 5-4 victory at Toronto.
"He can carve you up," Blue Jays manager John Gibbons said. "He has that nice cutter that he runs inside to the right-handers and really kind of neutralizes you in a lot of ways, and then can go to the outside part of the plate. He keeps you off-balance, and he's sneaky."
Wilson has also baffled the A's during a three-start winning streak, holding them to a combined five runs and 14 hits in 21 2-3 innings. He has had his way with Coco Crisp (4 for 32), Kurt Suzuki (2 for 22), Donaldson (4 for 20) and Reddick (3 for 18).
Home Run Derby champion Yoenis Cespedes is 4 for 12 in their matchups, and is back in the lineup after he was scratched Sunday because of a sore right shoulder. He's batting fourth and is the designated hitter.
The Angels (72-77) could also be in for a long night against Parker (11-6, 3.55).
The right-hander has a 2.08 ERA over his last four outings, and is 9-0 in his last 19 starts since a loss at Texas on May 22. The last A's pitcher with a longer unbeaten streak was Lefty Grove with 21 in a row in 1931.
Parker, though, was knocked around in his last start against the Angels on July 28, yielding six runs and a career-worst seven walks in five innings of a game Oakland rallied to win, 10-6.
The Angels are coming off Sunday's 2-1 win at Houston and have won 17 of 23. MVP candidate Mike Trout walked and scored, becoming the first AL player in major league history with 70 extra-base hits, 30 stolen bases and 100 walks in a season.
Trout, though, is 1 for his last 15.