Use an opener or swing-man out of the bullpen
If the Phillies can't find success with any of the other options, they have a ton of depth that could give solid innings with some help from pitching coach Caleb Cotham and staff.
The 2023 season is a strong example of this, as the team opened the season with newly extended lefty reliever Matt Strahm as the fifth starter. Over 10 games, Strahm collected a 4.05 ERA as opposed to his 2.82 ERA out of the bullpen the rest of the year. It's unlikely that they repeat this tactic, but you never know.
While the former San Diego Padre might be too valuable to remove from the recently ranked No. 1 bullpen in baseball, there are other players within the organization that have starting pitching experience.
David Buchanan returned this offseason from the KBO after four solid seasons with the Lions. There, he earned a career ERA of 3.02 with a season-low ERA of 2.54 over 188 innings last year. The 34-year-old could bring some experience to the fifth starter position.
There is also Kolby Allard, a former top-five prospect for the Atlanta Braves who has spent the majority of his career pitching with the Texas Rangers. He is another arm who offers former top-end potential and a coachability factor that could lead the coaching staff to trust him.
Finally, there is always the option of an opener. Pitchers like Connor Brogdon, Michael Mercado, and Nick Nelson all fit the bill. While they are not on the active roster at the moment, rotation struggles in early April could lead to a quick change in strategy for the Phils.