Streaking Mexican lefty Jorge De La Rosa aims for a fifth straight victory on Tuesday night when the Colorado Rockies visit Houston for the second of two interleague games with the Astros.
The teams will head to Colorado's Coors Field for two more games on Wednesday and Thursday.
De La Rosa, who turned 32 earlier this season, was 2-3 for 2013 after dropping a 6-2 verdict to the Dodgers at Los Angeles on April 30.
He's been pristine in May, however, defeating the New York Yankees, St. Louis, San Francisco and Arizona while allowing just six runs in 20 hits across 23 1/3 innings.
His earned run average has dropped more than half a run during the streak, from 4.18 after the Dodgers loss to 3.40 after the Diamondbacks win.
He's 0-0 with a hold and a 6.00 ERA in eight meetings with the Astros.
For Houston, young righty Jordan Lyles faces the Rockies for the fourth time in his 51st big-league outing.
The 22-year-old was called up to Houston on May 2 and has made five starts this month, winning two of three decisions, including a 3-1 defeat of Kansas City on May 22.
In that game, he allowed a single run on six hits in six innings.
In 25 composite innings, Lyles has given up 31 hits and 16 runs while walking nine and striking out 20.
On Monday, Brandon Barnes drove in the game-winning run in the bottom of the 12th inning and the Astros defeated the Rockies, 3-2.
With Wilton Lopez (1-2) pitching for the Rockies, Matt Dominguez singled to start the inning. Ronny Cedeno pinch-ran for him and reached second on a sacrifice bunt by Marwin Gonzalez.
After Jose Altuve was intentionally walked with two outs, Barnes hit a ground- rule double to right to bring Cedeno home.
"I knew when I got it, I hit it well enough to get it down the line and I knew it was slicing a little bit," Barnes said. "It was a matter of staying fair."
Carlos Pena drove in two runs for the Astros, who snapped a three-game losing streak. Starter Bud Norris allowed two runs on eight hits and three walks over seven frames. Paul Clemens (2-2) pitched a scoreless 12th to pick up the win.
Carlos Gonzalez and Jonathan Herrera drove in one run apiece for the Rockies, who saw starter Jhoulys Chacin give up two runs on five hits and a walk while fanning nine in a no-decision.
"We have to find a way to win a game like that, so it's frustrating," Rockies manager Walt Weiss said.
The Rockies won five of seven games from the Astros in both 2011 and 2012. Houston last won the season series, 4-2, in 2010.
Houston leads the all-time series by two games, 81-79, since 1993.