HOUSTON -- Lucas Harrell pitched his first complete game and left fielder J.D. Martinez threw out a runner at the plate in the ninth inning to preserve the Houston Astros' 1-0 victory over the San Diego Padres on Wednesday night.
Matt Downs homered and Harrell finished a six-hitter by striking out Nick Hundley with the bases loaded.
The drive by Downs was one of only two hits by the Astros, who couldn't get anything else going against starter Clayton Richard (5-8).
Harrell (7-6) allowed four hits through the first eight innings, but things got dicey for the rookie after that.
Chase Headley singled to start the ninth and San Diego had runners at first and second with one out when Logan Forsythe singled into shallow left. Pinch-runner Alexi Amarista headed for home, but Martinez scooped up the ball and fired to catcher Chris Snyder in time.
Pinch-hitter Mark Kotsay walked to load the bases, but Harrell hung tough and whiffed Hundley to end it.
Harrell struck out seven and walked four. Previously, his longest outing was 7 1-3 innings.
Richard struck out five in seven innings, but couldn't get any run support to back up his solid night on the mound.
Martinez singled for Houston's first hit to open the second inning. The homer by Downs started the third inning before Richard retired the next 15 batters he faced.
He was replaced by Dale Thayer for the eighth inning and he picked up where Richard left off, setting down the next three Astros to make it 18 in a row.
Yonder Alonso, who returned to the starting lineup after missing the last three games with a sore knee, singled with one out in the second. But Houston turned a double play in that inning before Harrell pitched a perfect third to face the minimum through the first three innings.
He got into a bit of a jam in the fourth after walking Everth Cabrera with one out before Carlos Quentin drew a two-out walk. Alonso grounded out to end the inning.
The Padres also threatened in the fifth after a single by Forsythe before Richard singled with two outs. Harrell escaped again with a groundout.
That was the start of Harrell retiring 10 of 11 batters. First baseman Carlos Lee helped his cause when he dived to stop a grounder by pinch-hitter Chris Denorfia with his body, and crawled to retrieve the dribbling ball as he extended his leg on the base for the first out of the eighth.
NOTES: Houston 2B Jose Altuve was out of the lineup for the third straight game with a strained right hamstring. ... The teams wrap up their four-game series Thursday when San Diego's Andrew Cashner faces left-hander Dallas Keuchel.