The Astros are very aware of the fact that they need to find a way to limit the innings of Lance McCullers Jr. and Vincent Velasquez, if they want to be able to use those two pitchers in a potential playoff series. Recently there has been thoughts of a six-man rotation to limit the number of regular season starts for the young pitchers. However, this would not be done until the rosters expand in September when you would be able to carry an extra starting pitcher.
Both McCullers and Velasquez were not stretched out in the minors like the Astros would have wanted.