The visiting Athletics go for a fifth consecutive win and a three-game sweep of the Astros, who try to avoid a fifth straight loss Sunday afternoon.After scoring one run in opening 0-2, Oakland (4-2) appears to have found its groove. The Athletics have averaged 7.0 runs and hit a combined eight homers during their winning streak, and they stayed hot in Saturday's 6-3 victory.Coco Crisp, Jed Lowrie, and Seth Smith all went deep for Oakland, which went 4 for 8 with runners in scoring position. Lowrie is 9 for 15 with two homers, four doubles and four RBIs during the winning streak.The A's also got a boost Saturday from Bartolo Colon, who earned the victory in his first appearance following a 50-game suspension for a positive testosterone test in August."I had to take care of myself because there were a lot of new guys that I didn't even know," Colon said of facing the Astros. "The only guy that I know is Carlos Pena."Houston's relatively obscure lineup could be in for a rough road ahead if its early-season efforts are any indication. The Astros (1-4) have hit .183 and been outscored 25-6 during their four-game skid, and their 60 strikeouts through their first five games are the most by any team since 1921.Houston had struck out at least 13 times in each of its first four contests before fanning four times Saturday."I couldn't tell you how many it was yesterday or how many it was today," manager Bo Porter said when asked about the strikeouts. "What I do know is we lost the game.""These guys are going to hit. We have no doubt in our minds we are going to hit. It is just a matter of time."Things aren't about to get any easier with a matchup against A's No. 1 starter Brett Anderson (0-1, 2.57 ERA) in store. The crafty left-hander, though, was outdueled by Mariners ace Felix Hernandez on opening day, yielding two runs, four hits and four walks over seven innings of a 2-0 defeat."I was definitely impressed with Brett," catcher John Jaso told MLB's official website. "The lights come on, and it's a different guy out there. He's competitive, and he's throwing the ball hard. That performance that he gave out there, that's definitely one that deserves a win."Anderson has never faced the Astros and has no experience against any of their players except Pena, who is 3 for 8 with a homer. Pena, though, is batting just .167 (3 for 18) with seven strikeouts thus far.The Astros, meanwhile, give the ball to Lucas Harrell (0-1, 1.50), who yielded six hits over six innings of one-run ball but took the loss in Tuesday's 7-0 defeat to Texas. While Harrell fared well, he was outdueled by Yu Darvish, who came within one out of throwing a perfect game."Lucas was outstanding," Porter said. "Even the time he got into jams, he was able to make pitches to make the double play to get out of them."In his only career start versus Oakland, Harrell gave up one run, five walks and four hits over six innings, earning the win opposite Anderson during a 6-1 victory July 30, 2010, while with the Chicago White Sox.