SEATTLE -- With the exception of Jose Altuve hitting leadoff as he's done for all eight games this year, Astros manager Bo Porter continues to tinker with the lineup to try to find the right combination. That meant catcher Jason Castro was hitting third for the first time this season Tuesday against the Mariners.
Chris Carter (four games), Carlos Pena (two games) and J.D. Martinez (one game) have hit also hit third this year as the Astros have used eight different lineups in eight games.
"We're just trying to find the right combination and get guys into slots where they're going to be productive," Porter said.
Castro had never started a game higher than the No. 4 spot prior to Tuesday. The third spot is typically reserved for the team's best hitter, and the Astros are still trying to identify who that might be.
"It's obviously a great spot in the lineup," said Castro, who singled and scored in the first inning Tuesday. "A lot of action is going on. There's typically a lot of guys on base in front of you. Hopefully, getting this opportunity I can capitalize on it. It's somewhere I like to hi. I'll do any job they need me to do, and hopefully I can go out there and show them it was a good idea to have me in the three-hole today."
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.