Austin Gomber
This one honestly does not surprise me as much. Like I was saying about hitting in Seattle, it is very difficult to pitch in Colorado, only a handful of pitchers have ever really tamed the beast of Coors Field. Gomber was the Cardinals 4th round pick in the 2014 MLB draft and made his MLB debut in 2018 pitching in the rotation and bullpen. He was the only major league player that went back to Colorado in the Nolan Arenado trade after having a 1.86 ERA in 29 innings with St.Louis in 2020.
Gomber joined the Rockies rotation in 2021 and had a 4.53 ERA in 23 starts which isn't terrible for a Rockies pitcher. In fact that season he pitched better in Coors as he had a 2.09 ERA. That success however did not carry on with him, he struggled in 2022 and was ultimately removed from the rotation in the middle of the season. And so far in 2023, those struggles continue to mount, as he has a 6.70 ERA after 9 starts. And back to his splits at Coors Field, Gomber has an 8.75 ERA at home, it has been a difficult stretch for him.
Whether or not Gomber can turn things around is unknown, but looking at the other players the Rockies acquired for Arenado doesn't look promising for them. Elehuris Montero might turn out to be a quality hitter for them, but so far the other prospects have not done anything for them. Even if Gomber starts to pitch better it may not matter all that much when you're referring to who benefited the most from this trade. With Nolan Arenado now officially under contract and staying in St. Louis for a long time, this was a disaster for the Rockies, and Gomber struggling just adds insult to injury.