Infante smashed one of two Marlins' homers, and for the second consecutive game, all of Miami's runs were earned via the long ball. The Marlins hit three Monday night in a 4-0 win.
Infante's fourth-inning blast, two rows into the Crawford Boxes in left field, broke a scoreless tie, and an inning later, catcher John Buck drilled a liner to almost the same spot for a 2-0 lead.
That appeared to be all Sanchez would need. The righty was cruising along with a two-hitter until the sixth inning.
"I felt great," Sanchez said. "At the beginning, I felt comfortable, and that's important right now. I just tried to get ahead in the count with any hitter, just throw strikes and throw my best pitch in the right situation.
"We're fighting the whole game. So I'm OK. I don't feel bad. I threw seven innings and that was good for the team, helping them as best I can."
Houston pinch-hitter Marwin Gonzalez started a game-tying, sixth-inning rally with a roller past third. Jose Altuve followed with a one-out infield single to deep short and a two-out walk to Carlos Lee filled the bases.
But Sanchez seemed to have worked out of trouble when he got Astros right fielder Travis Buck to hit a bouncer to the right of Infante, who couldn't come up with it. He then compounded the error by throwing wildly to first base, allowing two runs to score.
"I didn't get it and then I tried to hurry," Infante said. "It didn't feel comfortable when I threw it. I feel real bad for Anibal."
Sanchez went seven innings and took a no-decision despite allowing no earned runs. He struck out eight and walked two while yielding five hits.
But he certainly wasn't putting the blame on his otherwise slick-fielding infielder.
"That's part of the game," Sanchez said. "I'm not concerned about it. He's one of the best second basemen, the best hands in the Major Leagues.
"He's not perfect. He's human. I'm OK with that. I'm going to support him and get ready for tomorrow. Today we lose. There's nothing we can do."
Sanchez said he felt he executed the gameplan against Buck.
"We were trying to keep the ball down," Sanchez said. "I think we have very good infielders. So I just tried to keep the ball down, get a ground ball.
"What happened to Infante in that situation is very unusual. For me, he's one of the best second basemen."
Buck said he gave it his all to reach first base after his infield bouncer.
"You put the ball in play, you've got to run hard down the line," Buck said. "With the bases loaded, I didn't hit the ball all that hard, but I was busting it down the line. I put pressure on the defense. It was huge."
The Marlins lost it in the eighth inning when Buck delivered a two-out single off Webb (1-1) and scored on a double by Brian Bogusevic.
"When you pinch-hit, you have to be aggressive," Bogusevic said. "There's no time to see pitches. You get the first good one you see and try to put a good swing on it."
It was the Astros' first extra-base hit of the series.
"Since we left home, we've been pitching well and playing pretty good baseball," Miami manager Ozzie Guillen said. "Another great outing for Anibal, he threw the ball very well.
"We got the lead. Errors come with the game. I think we played well. I think they pitched pretty well, too. You've got to give credit to them. Their bullpen came out and did a tremendous job. And the kid [Houston starter Aneury Rodriguez] pitched well, too."
Rodriguez, an imposing 6-foot-4, 250-pound right-hander, didn't give up a hit until two outs in the fourth inning when Infante belted his homer. He went six innings, allowing just the two homers while striking out six in his first outing of the season after being called up earlier in the day from Triple-A.