The decision to return J.D. Martinez to Class AAA Oklahoma City before spring training was complete looks even stranger nearly two months into the season. Martinez was a late cut during exhibition play but has recently found a home as the Astros’ cleanup hitter. He’s held the position 12 times this season and entered Thursday 11-for-31 with three doubles, two home runs and seven RBIs since May 21. The 25-year-old continues to be inconsistent. Martinez struck out five times in five at-bats Monday and dealt with an in-game benching earlier this year. But on a team lacking proven power hitters and run producers, the third-year player is one of the few game-changing bats on the 25-man roster. Martinez went 2-for-4 with a go-ahead RBI single Wednesday during the Astros’ 6-3 win against the Rockies. He led the Astros in RBIs (55) last season and has displayed a smoother, more confident approach at the plate since rejoining the club May 6. “It goes back to him using the whole field. Guys that have the ability to drive in runs, when they get in trouble it’s because they’re basically trying to pull the ball to their pull field,” Astros manager Bo Porter said. “J.D. has done a great job of using the whole field, driving the ball the other way and taking what the opposition’s been giving him.”