"My numbers weren't good, but I feel like I swung it good early on and now I'm starting to find some holes," he said. "I've been working on a few things mechanically with [hitting coach John] Mallee. I've stuck with that approach, and it's starting to work out."
Astros manager Bo Porter said he knew when Dominguez started to hit the ball the other way with authority that he was coming around.
"That lets me know he's staying on the ball and he's hitting the ball hard to all fields," he said. "You look at his strike-zone discipline and it is much improved from last year and it buys him some more fastballs to hit. And he's a really good fastball hitter."
The trick for Dominguez now is keeping it up.
"That's what makes guys in the big leagues superstars, are the ones that can do it day in and day out, every single day," he said. "The mechanics are there, the approach is there. It's been going good lately."
Brian McTaggart is a reporter for MLB.com and writes an MLBlog, Tag's Lines. Follow @brianmctaggart on Twitter. This story was not subject to the approval of Major League Baseball or its clubs.