He'll have a chance to show his mettle as a starter on Wednesday, when the Rockies and Cardinals meet for the third game of a four-game series at Busch Stadium.
Guthrie won't be subject to the Rockies' 75-pitch limit for starters, and manager Jim Tracy won't reveal if this is just a spot start or a chance for Guthrie to prove his worth for the rotation.
Regardless, the right-hander is looking forward to the chance to start again.
"It's another opportunity, and I know in baseball. nothing is guaranteed, no matter how much experience you have, what you may or may not have accomplished," Guthrie said. "I've taken every outing, whether they've been good outings or bad outings, and been grateful for them. I continue to feel the same way. I have a chance to start again, and hopefully that will lead to many, many, many more starts."
Guthrie gave up 15 homers in his first 11 starts. In that June 17 outing, he gave up three runs on eight hits in three innings. As a reliever he had a 4.38 ERA in 12 1/3 innings, but he allowed six earned runs in his last six innings.
He said that his work in the bullpen helped him focus on some mechanical issues.
"Nobody can guarantee an outcome, but it's the preparation that gives you the belief that tomorrow is going to be a better day than the last," he said. "Ultimately, fans want the results, and that's what they deserve. But nobody here can promise them."
Cardinals starter Adam Wainwright will also be looking to get back on the right track.
Before a rough start against the Pirates on June 29, Wainwright had put together a three-start stretch of throwing seven innings and giving up two runs or fewer. But against Pittsburgh he allowed seven runs on a season-high 11 hits in five innings.
After posting a 7.32 in four April starts, Wainwright has lowered his ERA to 4.75.
"He was fighting it early on, but now he's got a real nice streak going here of knowing what needs to do and then going out and executing it," Cardinals manager Mike Matheny said. "When he does that, his stuff takes over at that point and he?'s got the ability to really take over the game."
Cardinals: Carpenter to undergo season-ending surgery
After continuing to feel numbness and weakness due to thoracic outlet syndrome, right-hander Chris Carpenter will undergo season-ending surgery on July 19 in Dallas.
"I want to pitch again, and this is the way for me to pitch again," Carpenter said. "We tried since Spring Training to get this going, and every time I tried to come back, unfortunately, it just doesn't allow me to do that."
The usual recovery time, according to general manager John Mozeliak, is three to six months. That would make Carpenter available for the start of Spring Training next year.
Since Carpenter's condition is caused by a nerve issue, Mozeliak said, the operation is fairly simple.
Carpenter threw 237 1/3 innings for the Cardinals in the regular season last year, posting a 3.45 ERA. He didn't pitch at all this season.
Rockies: Pitch-count limit more flexible
Tracy has said that he's willing to relax the 75-pitch limit for his starters if they're looking strong through the middle innings. He wants to make sure he has the flexibility to leave a starter in for a few more pitches in order to get to late-game relievers Matt Belisle and Rex Brothers.
On occasion, Rockies' starters have gone over the limit. To account for the extra pitches, those starters had shorter bullpen sessions before their next start.
"When the information comes back to me in my office that says [a pitcher] feels great, he's doing fine, that's what you're encouraged by," Tracy said. "You think as we go along here, the volume can increase."
Todd Helton has the most career at-bats against Wainwright of any of the Rockies, going 5-for-13 with two doubles against him.
Matt Holliday hit a two-run shot in the first inning on Monday, giving him homers in both games against his former team in this series.