OAKLAND, Calif. (AP) -- Astros first baseman Chris Carter remained one of the hottest hitters in the AL this month after homering against his former team.
The rest of Houston's lineup managed just five hits -- all singles -- and the pitching wasn't much better.
Carter hit his 20th home run, providing the lone bright spot in the Astros' 13-1 loss to the Oakland Athletics on Thursday.
The Houston first baseman is hitting .323 with six home runs and 15 RBIs in July.
"It's just good to have success against them," said Carter, who spent his first three seasons in Oakland. "Last year they beat up on us pretty good. I think the next following years we'll be better and it'll be more of a battle between us."
The Astros' second straight loss to the division-leading A's wasn't even close.
Brandon Moss hit a grand slam and Jed Lowrie had three hits to support starter Jeff Samardzija.
Samardzija (2-1) gave up a leadoff single to Jose Altuve and then retired 10 straight before Carter's home run on a first-pitch fastball with one out in the fourth. Samardzija did not walk a batter, struck out six and retired 12 of 13 following Carter's blast.
"The reason they went out and got Samardzija is because he could give them games like he gave them today," Houston manager Bo Porter said. "(He) gave them eight strong innings and pretty much had complete command of the game."
Scott Feldman (4-8) lost his straight start, lasting 5 1-3 innings. He allowed six runs on nine hits, walking five and striking out four.
Feldman allowed at least six runs for just the third time this season but for the second time in three starts. He's allowed 16 runs on 27 hits over his last 17 2-3 innings.
"It was a battle for him all day," Porter said. "Early in the game he really had his breaking ball working, and they started laying off and made him come back into the zone."
The A's were already ahead 4-1 entering the sixth when Moss delivered his third grand slam of the year.
Feldman walked Eric Sogard and gave up a single to Coco Crisp before striking out John Jaso. Anthony Bass replaced Feldman and hit Josh Donaldson to load the bases ahead of Moss. Lowrie also drove in a run in the inning.
Stephen Vogt added a three-run double in the eighth. Josh Reddick, who had a pair of doubles, added a sacrifice fly.
Donaldson and Derek Norris, who had three hits, each drove in runs in the third. Sogard scored on a wild pitch. Crisp's sacrifice fly in the fourth put the A's ahead, 4-1.
NOTES: Houston finished 2-4 on the six-game road trip. ... LHP Dallas Keuchel (9-6, 3.29) starts for the Astros at home against the Miami Marlins, which begins a 10-day, 10-game homestand, the longest of the season. ... Carter has an extra-base hit in each of his past four games, a season-best. ... Jose Altuve went was 2 for 4 against Samardzija after entering the game 1 for 11 against him.
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