HOUSTON (AP) — The Houston Astros will have to make some decisions about their rotation soon with ace Dallas Keuchel nearing a return from the disabled list.

The way Brad Peacock has been pitching lately, he's going to make those decisions much more difficult.

Evan Gattis homered twice to back up a solid start by Peacock and help the Astros to a 6-2 victory over the Seattle Mariners on Tuesday night.

Peacock (8-1) allowed three hits and one run while fanning nine in seven innings to tie the longest start of his career and earn his fifth straight win. Afterward, manager A.J. Hinch was asked where Peacock fit in when Keuchel returns.

"Competition is a good thing ... there's a conversation as to where to best utilize our weapons," Hinch said. "Whether it's in the rotation or in the bullpen, he's been effective in both. We haven't even broached that conversation."

Peacock isn't too concerned about what role he'll play when Keuchel is healthy. He's just glad to be pitching so well.

"Yeah, I'm not worried about it. I'm just happy to be here," he said. "Happy to have a job here on a first-place team, pitching on a first-place team. That's all you can ask for."

Seattle manager Scott Servais raved about Peacock's performance.

"He was ahead in the count, he was at the bottom of the strike zone, he was on the edges," Servais said. "We didn't get a whole lot of really good pitches to hit."

Gattis hit solo shots in the second and sixth innings off Sam Gaviglio (3-5) for the eighth multihomer game of his career.

Luke Gregerson got the last four outs for his first save.

Jose Altuve had three hits and drove in a run for the AL West-leading Astros, and Marwin Gonzalez added a hit in his first game at shortstop since All-Star Carlos Correa was placed on the disabled list with a torn thumb ligament on Tuesday.

Gaviglio allowed eight hits and five runs in six innings after being recalled from Triple-A Tacoma on Tuesday.

Houston took a 1-0 lead on a sacrifice fly by Yuli Gurriel in the first inning.

Leading by two after Gattis' first homer, Gonzalez singled to start Houston's fourth and advanced to second on an error by Gaviglio with one out. A double by Nori Aoki came next to score Gonzalez, and a two-out RBI double by George Springer extended the lead to 4-0.

Peacock retired 12 of the first 13 batters he faced before Kyle Seager led off the fifth with his 200th career double. He advanced to third on a groundout by Danny Valencia and the Mariners cut the lead to 4-1 on an RBI single by Jarrod Dyson.

Gattis extended Houston's advantage to 5-1 with his full-count shot to left field with two outs in the sixth inning.

Houston added a run on an RBI single by Altuve with one out in the seventh.

TRAINER'S ROOM

Mariners: OF Mitch Haniger was out for the third straight game after injuring his right index finger on Saturday night. Servais said he was feeling better Tuesday and would likely play on Wednesday.

Astros: Correa is expected to miss six to eight weeks because of his thumb injury that will require surgery. The Astros put Correa on the 10-day disabled list Tuesday, a day after he hurt himself taking a swing against Seattle. They expect to have him back in the lineup for the stretch run in September. ... RHP Collin McHugh (elbow) will come off the disabled list to make his first start of the season on Saturday against Baltimore. RHP Joe Musgrove will move to the bullpen to make room for McHugh in the rotation. ... Keuchel (pinched nerve in neck) felt good a day after his first rehabilitation start for Double-A Corpus Christi on Monday night. Hinch said Keuchel will throw a bullpen on Wednesday before they decide what the next step will be.

THEY SAID IT

Hinch on the two-homer performance by Gattis: "They come in bunches. He can get hot with the best of them and he can ambush you and he can really do some damage."

UP NEXT

Mariners: James Paxton (8-3, 3.19 ERA) will start the series finale for Seattle on Wednesday. Paxton allowed five hits and two runs in six innings of a win over the Chicago White Sox in his last start.

Astros: Charlie Morton (7-3, 4.06) is scheduled to start on Wednesday for Houston. Morton got the win in his last start by yielding three hits and five runs in five innings of a victory over Minnesota.