"It's extremely disappointing, just because I couldn't help the guys out like I normally do," said Keuchel, a front-runner for the AL Cy Young award. "I know they were kind of leaning on me to kind of go out there and perform. That's a good lineup right now."
Keuchel (17-8) ended a club-record run of 40 starts of least six innings when manager A.J. Hinch patted him on the chest with two outs in the fifth and took the ball with the Rangers leading, 9-0. Keuchel gave up homers to Mike Napoli and Rougned Odor in the first, and Prince Fielder in the third.
Keuchel, who entered the game with an AL-best 2.22 ERA, saw that number climb to 2.56, with Toronto's David Price taking over the league lead at 2.42 after allowing one run in seven innings in a win over Atlanta on Wednesday.
"I just told him I appreciate his effort," Hinch said. "This guy has been terrific for us all year, and even trying to get the last out, I really wanted him to leave the game on his own, getting the outs, and they put together an inning and he was trying. I just told him, 'It just wasn't [your] day.' I did appreciate how he went about it. Even after the six-run inning, he came in, he was the same in the dugout preparing, talking through the hitters."
Hinch said that the Rangers "ambushed" his ace in the first inning, knowing he was a strike-thrower who was going to be around the zone. He elevated some pitches, as well.
"It seemed like every ground ball found a hole, every ball in the air went to the wall or went out of the park, which is unusual for Dallas," Hinch said. "They had a very aggressive approach to him. He made a little bit of an adjustment with some secondary pitches. Fielder hits the homer, and then he ran into trouble in the fifth.
"All in all, they had a good game plan, they executed, they found some holes, hit some homers. Six runs in the first is unusual for any of our starting pitchers, specifically Dallas, and that was tough to come back from, and we didn't even counter."
Keuchel hasn't pitched as well on the road as he has at home, where he's unbeaten, but he had gone 1-0 with a 1.23 ERA in three starts against the Rangers this season.
"Dallas is a great pitcher," said Rangers center fielder Delino DeShields, a former first-round pick of the Astros. "He kind of laid into us last time we faced him. We want for sure to send a message. But more important, we have a lot of energy and do whatever we can to win the ballgame."