The Rockies look to avoid a third straight loss while trying to hand the Astros a fourth consecutive defeat Monday.
Colorado (27-23) won six of seven before losing two straight in San Francisco. One day after the Rockies blew a 4-0 lead in a 6-5, 10-inning loss to the Giants, they lost an early two-run advantage in Sunday's 7-3 defeat.
The Rockies are 11-14 away from home and have not won a road series this month.
They're also 2-4 in interleague play this season, and though Houston (14-36) has the AL's worst record, it's won nine of 14 over the Rockies at Minute Maid Park.
"This is still the big leagues, and you've got to respect whoever lines up against you," manager Walt Weiss told the Rockies' official website. "Houston might be struggling now, but if we don't go down there and play the game hard, play the game right, we'll go down there and get beat twice."
Colorado's Carlos Gonzalez is batting .400 (20 for 50) with six homers and 15 RBIs during an 11-game hitting streak versus Houston. He posted three straight multi-hit games before going 0 for 5 with three strikeouts Sunday.
Three big innings have cost scheduled Rockies starter Jhoulys Chacin (3-3, 4.10 ERA) in his last two outings.
Staked to a 6-0 lead, the right-hander allowed five runs in the fourth and three in the sixth of an 8-6 loss to San Francisco on May 16. He then failed to hold a 4-0 advantage and gave up four runs in the seventh inning of a 5-4, 10-inning win over Arizona on Tuesday.
Chacin was 3-0 with a 1.46 ERA in his four starts before missing two weeks with a lower back strain. Since returning, he's 0-3 with a 6.85 ERA in four outings.
Eleven of the 17 walks Chacin has issued have come over those last four.
"If they're going to get on base, they have to be hitting the ball," he said. "Even if I have to throw it right in the middle."
Chacin is 1-1 with a 3.46 ERA against the Astros, who appear confident Bud Norris (4-4, 3.86) will start Monday despite lingering back problems.
Norris allowed five hits through six scoreless innings before back tightness forced him to leave Tuesday's 7-3 home loss to Kansas City.
"It's just making sure you're stretched and loose so that your body isn't cold when you get out there so you don't pull something," he told the Astros' official website.
The right-hander is 1-3 with a 7.71 ERA on the road, but 3-1 with a 1.93 ERA in six home starts.
He's 0-1 with a 17.55 ERA in two starts at Colorado, but allowed a two-run homer and three other hits while striking out eight in seven innings of a 3-2 win last season - his only home appearance against the Rockies.
With four hits in Sunday's 6-2 loss to Oakland, Houston catcher Jason Castro is 10 for 12 with two homers and four RBIs in four games.
It's uncertain if Colorado's Michael Cuddyer will play after he left Sunday's game with a bruised right forearm. He was activated off the disabled list Friday from a back injury.
After two games in Houston, the clubs play Wednesday and Thursday in Colorado.