"That's pretty much it," he said. "I just tried to simplify things. I made an adjustment back in Seattle and have been happy with it since."
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Castro, in his sixth season and the longest-tenured player on the Astros, was hitting .321 (17-for-53) in his previous 18 games prior to Saturday. In that span, he had a .455 on-base percentage with 13 walks and only 18 strikeouts. He leads all American League catchers in walks (20) and on-base percentage (.359).
"He's had a good month here," Astros manager A.J. Hinch said. "Most of it is about controlling the strike zone. He's walked more in recent weeks. He's used the whole field a little bit better. He's had a little bit better at-bats against left-handed pitching. I think his overall offensive production, there's a quieter approach to him and a better pitch selection for his performance. It's nice to have him warm up at the bottom of the order and really start to set up the top of the order for more run-scoring opportunities."
Castro swung the bat well in the spring, and he admits his early-season performance was wearing on him mentally. He's been through these kinds of things before and kept working until he finally found something that clicked.
"It seems like every year there's some sort of adjustments to be made, and even within your certain kind of segments of the year, teams will start to adjust to you based on what you've done so far up to that point, what other teams have done against you," Castro said. "There's a kind of back and forth, and it really never stops, no matter how long you've been around.
"Once you make an adjustment to something, they'll adjust back to something else. It's never attainable to where you're like, 'I'll be good. I don't have to make adjustments anymore.' It's constantly that back and forth between pitchers and a hitter, and it's just kind of the nature of the game."
Brian McTaggart has covered the Astros since 2004, and for MLB.com since 2009. Follow @brianmctaggart on Twitter and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.