RHP Lucas Harrell didn’t need much offensive support while dominating the Seattle Mariners, but he got plenty of cushion as Ronny Cedeno and Brandon Laird each hit three-run home runs in the Astros’ 10-3 victory Wednesday afternoon. Chris Carter got the attack going with a leadoff home run in the second inning on an afternoon that also was highlighted by Cy-Fair High graduate Robbie Grossman’s impressive major league debut at Minute Maid Park. Grossman had a pair of doubles, becoming only the second Astro to debut in the majors with at least two doubles. Laird was 3-for-4 with four RBIs. Cedeno was 3-for-4 with three RBIs and two runs. Cedeno gave the Astros a 4-0 lead with his three-run homer to left in the fourth inning. Grossman scored his first major league run in the fifth to make it 5-0 on Laird’s double. Matt Dominguez hit a two-run double, and Laird drilled his three-run homer during the Astros’ five-run rally in the sixth inning. Harrell scattered six hits and five strikeouts while holding the Mariners to one run and one walk over seven strong innings.