Castro is hitting .385 with three homers and 10 RBIs during his streak. His homer was his 10th of the season, giving the Astros eight players with double-digit homers, one shy of the club record.
"His timing has been great," manager A.J. Hinch said. "He's been very disciplined. He's laid off some below-the-zone breaking balls, secondary pitches. He's put the barrel on the ball pretty consistently. There's a lot of confidence in him right now. He's carrying himself with a lot of confidence in the batter's box."
Castro pulled a double to right field in the second inning and launched his towering grand slam to right in the fourth, cutting Texas' lead to three runs.
"We're looking at a pretty big deficit there, and it kind of gave us more hope, and I thought we did a good job with the bats, kept pushing all night long and didn't give in," Castro said. "We were doing everything we could to try to come back."
Brian McTaggart is a reporter for MLB.com and writes an MLBlog, Tag's Lines. Follow @brianmctaggart on Twitter and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.