5. Daniel Palencia
23-year-old Daniel Palencia is about to be one of the most important arms in the Cubs bullpen. Michael Fulmer recently went down with an injury and landed on the 15-day IL. This means Palencia will be called on in higher leverage situations, where he will have to prove why he is thought of as one of the best arms in the system. The velocity is certainly there as the flamethrower regularly touches 98-100 mph on his fastball.
Control is what Palencia lacks at times as he's walked 12 batters in 15.1 innings this year. However, he's also struck out 14 and held opponents to a .173 batting average. Palencia's 4.11 ERA is also deceiving as he's only given up earned runs in three of his 16 outings this year. I foresee this guy being around for a long time and it's really great to see more than one high-velocity guy out of the bullpen. Julian Merryweather's fastball sits in a similar high 90s range and Alzolay can also reach 97mph at times but other than that, the pen lacks Palencia's type of velocity.