Entering Friday's game against the Cardinals, the powerful Houston left fielder had a batting average of .105 in his last six games, with only a pair of singles in 23 plate appearances. That's dropped his average for the young season from .313 to .267.
But Martinez doesn't appear to be pressing, with several hard-hit balls of late. He's also maintained his plate discipline, walking four times in that six-game stretch.
Manager Brad Mills doesn't appear overly concerned, either. He stuck with Martinez as the No.3 hitter in Friday's lineup, which is where he's been for almost the entire season.
"J.D. is one of those guys that works on things every day," said Mills. "I don't care if he's hitting .500 for the last month and a half. He goes out and always works, always tries to get better. That's just him.
"He was in the cage early this afternoon working on some things. What they were particularly, I'll let him and our hitting coach [Mike Barnett] take care of that.
"I only get concerned if it feels like it's wearing him down."
The struggles haven't been to the detriment of the Astros, who won four of those six games.