Obviously, all this is happening because the Pirates' pitchers can't stay healthy. But in a strange way, it's nice to see Locke get some playing time, since he's pretty clearly a big-league caliber pitcher. The end to his 2013 season was frustrating, but it's somewhat rare to see a pitcher who played as well as Locke did in 2013 have to begin the next season in the minors (which would have happened whether or not Locke himself had been hurt).
Anyway, let's hope Locke pitches well, since the Pirates aren't exactly loaded with good options behind him. I wouldn't be surprised if we ended up seeing Jake Brigham pitch in the majors at some point this year, for example.