The six (likely) locks - righties David Bednar, Colin Holderman, Wil Crowe, Duane Underwood Jr., Chase De Jong, lefty Jose Hernandez
Some of these are rather obvious. David Bednar is coming off an All-Star season. Since joining the Pirates in the Joe Musgrove trade, the Pittsburgh native has spent the past two seasons developing into one of the more reliable relievers in the National League.
While Wil Crowe struggled in the second half last season, he was borderline dominant in the first half. Colin Holderman came to the Pirates in the Daniel Vogelbach trade and flashed some good things before a season-ending injury. Both will get an extended look, at least to start the season, to see what they can do. It should also be noted that Holderman has added a pair of pitches to his repetoire this spring, adding to his potential.
Duane Underwood Jr. and Chase De Jong are both out of minor league options. Combine this with Underwood Jr.'s potential and De Jong coming off a career year, and both head north. Underwood Jr. needs to find consistency and De Jong needs to prove last season was not a fluke to remain in the bullpen for the entire season, but both will be given the opportunity to do just that.
That brings us to Jose Hernandez. Acquired from the Los Angeles Dodgers in the Rule 5 Draf, Hernandez is the only healthy left-handed reliever on the team's 40-man roster. Even if this was not the case, with the 100+ MPH fastball he has flashed this spring Hernandez would likely get a spot regardless.
Hernandez's stuff is simply too good to not give him an opportunity. Hernandez appears to have the ceiling of being a plsu, potentially dominant left-handed reliever. The Pirates need to give him every opportunity in the world this season to see if he can develop into a long-term bullpen piece.