Jeremy Guthrie has made Opening Day starts before, but tonight's assignment with the Rockies could be one that gets his career back on track.

Guthrie makes his proper Colorado debut on Friday in the opener of a three- game series with the Houston Astros.

The right-handed Guthrie spent his previous five seasons with the Baltimore Orioles and made three Opening Day starts in that span, including last year's win over the Rays. However, that victory, which featured eight scoreless innings of three-hit ball, did not kick start a great campaign for Guthrie, who lost his next six decisions en route to a 9-17 record over 34 appearances. That losing mark came with a 4.33 earned run average, just the second time in five years with the Orioles that the righty did not post an ERA under 4.00.

Guthrie is set to turn 33 on Sunday and is hoping to get his career back on track after becoming just the second pitcher in major league history to lose 17 games in a season twice.

Colorado is turning to the former first round pick on Opening Day after dealing away former ace Ubaldo Jimenez to Cleveland last season and losing rising star Jorge De La Rosa to Tommy John surgery last May. The Rockies dealt starter Jason Hammel and reliever Matt Lindstrom to the Orioles to add Guthrie's right arm tot he rotation.

"To the credit of my teammates, we always had confidence in Baltimore that we had a good team," Guthrie told Colorado's website. "There's no difference.

"This team is preparing each day to compete for the division and make a long run in the playoffs if we can accomplish the first goal. In Baltimore we were all professionals. We practiced each day to compete."

Guthrie, who is making the jump for the first time to the National League, has faced the Astros just once before and got a no-decision despite allowing on run on three hits over eight innings with eight strikeouts.

While Guthrie will be making his Rockies debut, first baseman Todd Helton is expected to make his 15th straight Opening Day start. He is part of Colorado's core that includes young outfielder Carlos Gonzalez and All-Star shortstop Troy Tulowitzki and added outfielder Michael Cuddyer, second baseman Marco Scutaro and catcher Ramon Hernandez this offseason.

Expected to contend for the National League West title last year, the Rockies instead struggled after a fast start and finished 21 games off the pace with their first losing season in three years.

Still, it wasn't half as bad as the Astros season was.

Houston lost 106 games in 2011 and finished 40 games back of first place. It will hope for a better campaign this year in what is the club's 50th anniversary season.

The most significant changes to the Astros, who are set to move to the American League in 2013, came off the diamond. A group headed by Jim Crane purchased the team from Drayton McLane and general manager Ed Wade was dismissed. Taking over for Wade is former Cardinals executive Jeff Luhnow.

Changes figuring to be coming for the Astros, but their longest-tenured player will get the start on Opening Day.

Wandy Rodriguez enters his eight season with the Astros and will be the first left-hander to start Opening Day for the Astros since Dave Roberts in 1974. Rodriguez is a solid choice after going 11-11 in 30 starts last year with a 3.49 ERA. The 33-year-old has posted an ERA under 4.00 in each of his past four seasons.

Rodriguez is 4-3 with a 4.43 ERA in 11 career starts versus the Rockies and will be the third different pitcher to start Opening Day for Houston in the past three seasons. Roy Oswalt held the honors in 2010, while Brett Myers did so a season ago. Myers opens his third season with the Astros as their closer.

The Rockies won five of seven over the Astros last season, with the clubs splitting a four-game set in Houston from Sept. 22-25.