The Tigers go for their seventh straight win over the league-worst Astros on Tuesday night at Comerica Park.After losing four of five to fall into a first-place tie with Cleveland in the AL Central, Detroit (21-15) took the opener of this series 7-2 on Monday to regain a half-game lead following the Indians' doubleheader split with the Yankees.The Tigers now look to continue their dominance of the Astros (10-29) with Fister (4-1, 3.14 ERA) on the mound after outscoring them 44-10 in winning each of the first five meetings this season.After limiting opponents to three runs or less in each of his first six starts, the right-hander gave up five runs and eight hits over three innings in a 5-4 loss at Washington on Thursday.It was his shortest start other than an outing in 2011 when he was taken out after two innings because of a lengthy rain delay."It was just lack of executing," Fister said. "I didn't keep the ball down. I got a lot of the plate a lot of the time and they made me pay for it."In his only career start against Houston, Fister did not receive a decision after allowing three runs and a season-worst nine hits over six innings in a 4-3 win May 3.The Astros, who have dropped 12 of 13 on the road, will try to avoid matching a season high with their sixth straight defeat overall.Harrell (3-3, 4.67) allowed eight runs and 10 hits over 4 1/3 innings in a 17-2 loss to the Tigers on May 4, but he's 3-0 with a 1.82 ERA in his other five starts since mid-April.Miguel Cabrera, Torii Hunter and Omar Infante each had two hits in as many at-bats against the right-hander in that rout, with Cabrera hitting a two-run homer. Cabrera had his 11-game hit streak end Monday when he went 0 for 4.Harrell, who makes his first start at Comerica Park, will try to give Houston a lift a night after top starter Bud Norris went down after five innings with lower back spasms.Harrell won't have to deal with center fielder Austin Jackson after Detroit placed its leadoff man on the 15-day disabled list because of a pulled hamstring Monday.Don Kelly was in center field and Andy Dirks went 3 for 4 with his first career grand slam while filling in at the leadoff spot."I've hit leadoff in college and I've hit leadoff in the big leagues and in the minor leagues," Dirks said. "It's really nothing different."Houston may also be missing a key part of its lineup after second baseman Jose Altuve left with a jaw injury following a collision with right fielder Jimmy Paredes in the second inning Monday.Altuve has been a bright spot with a team-best .333 batting average, and he went 3 for 4 against Fister on May 3."Altuve came out for precautionary reasons, and he's already told me that he's playing tomorrow," manager Bo Porter said.Porter's club has struggled against Detroit this season with a .181 batting average and seven extra-base hits.