Holmes was called up Monday to replace Joe Musgrove, who went to the 10-day disabled list with a shoulder injury, Bill Brink of the Pittsburgh Post-Gazette reports.
Holmes joined the Pirates as the 26th man for their Sunday doubleheader against the Tigers but did not get the opportunity to make his major-league debut. Musgrove's stay on the DL could be short, but Holmes should at least receive his first major-league action at some point in the next week. The 25-year-old is a potential future back-end starter who posted a 3.36 ERA in 112.2 innings for Triple-A Indianapolis last season, though his stay on the roster is likely to be short, barring further injuries, which limits his fantasy relevance. Holmes could receive Musgrove's scheduled start on April 5, though it's more likely that the opportunity goes to Steven Brault or possibly Tyler Glasnow.