"I was terrible," said Harrell, who allowed seven hits, a career-high six walks and two runs in five innings. "I felt like the first two innings, I was trying to get a feel for the game. It felt like I had never picked up a baseball before. It was embarrassing. It was bad."
Harrell (10-11) hasn't won since holding the Cubs to six hits and one run in eight innings on Aug. 14 at Wrigley Field, going 0-3 with a 4.14 ERA in his last seven starts. With a career-high 187 2/3 innings under his belt, the Astros will try to squeeze five more out of him next week in Chicago.
"Since I've been here, he's been a horse," Astros interim manager Tony DeFrancesco said. "He can finish strong. They've got a pretty good team over there. He got in some trouble but he battled through it, and we got him out after the fifth inning."
Harrell doesn't think pitching in a six-man rotation, which often means going once a week when there's an off-day, has done him any favors. But one of the reasons the Astros went to a six-man rotation was to conserve Harrell's innings.
"For me, it's a little too much time [between starts]," he said. "I'm a touch-and-feel guy. I need to be out there a lot and it's something I didn't think would be a problem. I don't know if it's gotten in my head or it's been one thing I haven't been out there a lot. Basically, I've just struggled. If you look at my last five starts, they've been really bad."
Cardinals starter Jaime Garcia (6-7) threw seven scoreless innings to win his second consecutive start against the Astros. The victory was the Cardinals' 10th in a row this year against Houston, which is their longest in the 51-year series history between the clubs.
The teams, who dominated the National League Central in the late 1990s and early 2000s, will meet for the final time Wednesday as members of the NL. The final home game of the season for the Astros will represent their final NL game at Minute Maid Park, with the Astros moving to the American League in 2013.
Garcia lost his first five decisions against the Astros in his career before beating them in St. Louis on Thursday.
"I'm not going to lie to you and say I didn't think about it, that every time I come here it hasn't been good," Garcia said. "But at the same time, when I go out now, all I'm worried about is making one pitch at a time and helping my team win."
The Cardinals loaded the bases with one out in the first inning and managed only a Yadier Molina sacrifice fly. Jon Jay singled home a run in the second, and Harrell walked the next two batters to load the bases again. Allen Craig grounded out to end the inning.
The first two batters reached in the third, but Harrell got an inning-ending double play off the bat of Pete Kozma.
In the fifth, St. Louis loaded the bases with no outs, and Carlos Beltran hit into a 3-2-3 double play. Harrell intentionally walked Daniel Descalso to load the bases for Kozma, who was robbed of a hit on a terrific diving stop by Jose Altuve to end the inning.
"I got lucky," Harrell said. "Beltran swung at a pitch out of the zone, 3-0. If he wouldn't have done that, I would have been in real trouble."
The Cardinals scored twice in the eighth against Hector Ambriz on an RBI double by Kozma and a fielder's choice by Jay.
DeFrancesco believes Harrell's recent struggles do nothing to diminish the solid season he's put together as a rookie. His home ERA of 2.34 ranks seventh all-time in ballpark history for a single season among pitchers with at least 75 innings pitched.
"I really tip my hat to the kid," DeFrancesco said. "I think he's really showed us that he's a Major League pitcher and that he has a chance to be a good one. He's doing everything he can. In this game, you need a starter to go 200 innings, and he can be one of the guys that gives us quality innings, 200-plus innings. He had a great year."