After making a host of major moves well before the trade deadline, the Boston Red Sox  made their final move before the trade deadline, shoring up their bullpen with the acquisition of Minnesota Twins' lefty reliever Fernando Abad. The Red Sox didn't have to give up a ton to acquire Abad, although they did part ways with a promising young reliever in Pat Light, a late-innings reliever who boasts a fastball from 98-100 mph. Light was on Boston's AAA roster in Pawtucket. 

Abad balances Sox bullpen, adds lefty arm to strong bullpen

Having already acquired Brad Ziegler from the Arizona Diamondbacks, and closer Craig Kimbrel coming back from the disabled list, many Sox fans would have been satisfied with a bullpen that consisted of Junichi Tazawa,  Ziegler, and Kimbrel. However, the pick-up of Abad gives the Red Sox a lefty arm that can balance a righty-heavy bullpen. Abad boasts a 2.65 ERA in 39 appearances this year for the Twins, and he is just one year removed from a career-best season in 2014, when he put up sparkling numbers with the  Oakland Athletics. He is dominant against left-handed batters, who hit just .163 against Abad.

Righties have a .390 on-base percentage against Abad, so he will likely be a lefty specialist. He will also be excellent in keeping the ball in the ballpark, something the Red Sox needed in the later innings. Abad has surrendered just two home runs this season, over 34 innings. This is a valuable asset coming out of the bullpen for Boston, who can now mix and match Abad, Tazawa, Ziegler, and Kimbrel in the later innings, keeping the bullpen more rested. A fatigued bullpen has plagued the Red Sox at times this season. To make room  for Abad on the major league roster, the Red Sox optioned starter-turned-reliever Joe Kelly back to Pawtucket, where he will continue to learn the nuances of being a reliable MLB reliever. 

Red Sox give up bullpen prospect in Pat Light

The Red Sox got through the trade deadline, acquiring the pieces they needed, without giving up their 'untouchable' prospects in Yoan Moncada and Andrew Benintendi. To acquire Abad, they were forced to cough up a former first-round pick in Light, who has spent most of the season in Pawtucket. Light became a reliever in 2015, utilizing his blazing fastball in the back end of the bullpen. Light dominated in Portland, with a 2.43 ERA, earning a promotion.

Pat Light has dominated in AAA, but struggled in the majors. He will look for a chance to really break into the majors with the Twins. The Boston Globe 
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Pat Light struggled in Pawtucket, but posted brilliant numbers during winter-league ball, featuring a sparkling 1.59 ERA in 12 games. Returning to Pawtucket this season, Light appears to be nearly ready for the majors, hurling his way to a 2.32 ERA in AAA. He has struggled in two appearances with the big club, giving up 7 earned runs in 2.2 innings. Light is a strong pick-up for the Twins, who pick up a reliever with the potential to be a dominant late-inning reliever. Giving up Abad makes since for the Twins, as Abad is eligible for arbitration after this season and will likely demand an expensive salary in 2017. As the Twins continue to rebuild, Light could become an affordable replacement for Abad.