Drafted 18th in the 3rd round of the 2007 inaugural draft by the London Underground, Hernández had established himself as one of the elite closers of the game.  In his 3-year career, the nasty closer compiled 70 saves and more impressively, a .909 save percentage.  He boasted a career ERA of 2.10 and 1.00 WHIP.  Over his career, he held opposing batters to a batting average of .232 and possessed a 7.75 K:BB ratio.  Baseball News Network ranked him as the game's  top closer in 2009.

Serving as the closer of the Underground from 2007-2009, London fans synonymously linked Hernández to victories and 9th inning close-outs.  Despite serving as the de facto franchise closer, Hernández was traded on 12/15/09 to Connecticut along with an 8th round draft pick in exchange for middle reliever Chris McKinney, blue chip pitching prospect Francisco Robles, and a 7th round draft pick.  The trade was in due part to London's bullpen strength and emergence of young fireballer Luis Mora.  A small market team, London needed to balance out its salary books and spread its money evenly across the other positions.

Hernández's arrival to Connecticut brought a sense of security to late inning games for Nutmegger fans.  Ecstatic over its new closer, Hernández's fresh start ended abruptly as it started.  On 3/07/10 in a spring training game against Gloucester, Hernández suffered a torn labrum in his throwing shoulder that effectively ended his career.  Unfortunately for Connecticut, fans never got an opportunity to witness Hernández nail down a save for the team when it mattered.

With 3 years devoted to the red and black uniform of London, Hernández appropriately will always be remembered as an Underground.  A two-pitch pitcher, Hernández possessed a lively fastball and nasty late moving slider.  Appearing like a fastball, his slider's late break kept opposing batters confused and off-balance.  He threw in the low to mid 90s with impeccable control and top-notch movement.  He is indeed one of the great closers of the game and it is unfortunate that future generation of PEBA fans will never get to see Hernández shut the door on opposing teams.  Hernández exemplified what a prototypical closer should be.