Japanese left-hander Yusei Kikuchi improved his record since joining the Houston Astros in a midseason trade to 4-0 after six innings of work in an 11-5 win over the Arizona Diamondbacks on Saturday. Kikuchi (8-9), who was 4-9 with a 4.75 ERA for the Toronto Blue Jays until late July, gave up four runs on seven hits, two of them home runs, while walking none and striking out six. The 33-year-old left with a six-run lead at Minute Maid Park. His ERA with the Astros rose to 3.07. “I faced a lot of baserunners but got through six innings without allowing a big inning,” Kikuchi said. “I wasn’t in …