The St. Louis Cardinals have yet to announce who will replace John Gant (and Carlos Martinez, eventually) in the rotation. The easiest option would likely be to insert Wade LeBlanc into the rotation since he is somewhat stretched out and has a history of starting in the majors.
The other options are Jake Woodford, who has a 5.81 FIP in the bullpen, and a group of minor league starters. To begin with, if the Cardinals prefer an option that is already on the 40-man roster, Angel Rondon could be an option. The 23-year-old made his MLB debut earlier in the season, but his 5.23 FIP at Memphis does not inspire confidence that he would be able to handle a spot in the rotation.
Another option is Matthew Liberatore. The Cardinals’ top pitching prospect has posted a 4.54 FIP in seven starts at Memphis. This is better than Rondon. However, he is still just 21 years old, has made seven appearances above Single-A and has a fastball that lags behind his other pitches. All of these things suggest that it is too early to promote Liberatore.
A more unexpected solution could involve giving a chance to Connor Thomas. The Cardinals’ fifth round pick in the 2019 draft was promoted to Memphis after just four starts at Double-A Springfield where he compiled a 5.27 FIP and 3.23 xFIP, largely because of an inflated home run rate but good results elsewhere. At Memphis, the 23-year-old has tallied a 3.95 FIP and 3.65 xFIP in his first 24 1⁄3 innings. In his brief minor league career, the left-hander has shown an ability to generate ground balls, as well as strong control.
All three minor league pitchers have the same problem — they are inexperienced and probably not ready for the major leagues. However, the Cardinals need starting pitching if they are going to move Gant and Martinez into the bullpen where they belong. As a result, it appears more than likely that Wade LeBlanc will enter the rotation.
For now, the Cardinals intend to leave Martinez in the rotation. However, that is not likely to last long. Whenever the team does decide to remove Martinez, Matthew Liberatore will likely enter the rotation, barring any external acquisition. The combination of Liberatore’s prospect pedigree, and his ability to hold his own in Triple-A, as well as the Cardinals’ need for a starter, will likely lead to him being the choice.
Regardless of who takes the places of Gant and Martinez, the Cardinals will need to be conservative with the replacements on the mound. None of these pitchers are realistic season-long starting options for a team with playoff hopes. They will likely walk fewer batters, but they will also struggle at times. Wade LeBlanc is in his 13th MLB season and has tallied a career fWAR of just 3.2, while Liberatore is inexperienced.
Due to this, the Cardinals need to not push them too hard. Mike Shildt has shown a tendency this season to leave his starting pitchers in for close to 100 pitches or more. This should not happen with any of these pitchers. The Cardinals can get multiple innings out of most of their relievers, and with Gant, and eventually Martinez, moving to the bullpen, the Cardinals will have a pair of relievers who are stretched out for multiple inning assignments.
This will be beneficial when two new pitchers are entering the rotation. Mike Shildt should aim to get four or five solid innings from LeBlanc and Liberatore (or whoever takes the second spot), but should be willing to pull them earlier if needed. Then, pitchers like Gant and Martinez can cover the next two or three innings before handing the ball to the rest of the bullpen.
By doing this, the Cardinals will help LeBlanc and Liberatore adjust to life in the major league rotation, while also preventing opposing hitters from figuring them out and punishing them in later innings. By tag-teaming these starts, the team will hopefully be able to be competitive by dividing five or six innings among two pitchers. The starter will be given an easier role while the follower (Gant or Martinez) can attack hitters in shorter stints.
The two new starters should not be treated like players who are supposed to enter the rotation and fix it completely. They should be treated as players who are helping to stabilize the rotation in the short to medium term until the team can find improvements.
Gant and Martinez may not have succeeded in the rotation, but they could still have an important role to play this season for the Cardinals. Their ability to pitch multiple innings out of the bullpen could lighten the load on the two new starters, while also putting them in a position where they are more likely to succeed.