Josh Fields

The 32-year-old is a highly valuable major-league bullpen arm, but he's not quite a relief ace. While the surface numbers were stellar, the peripherals suggest Fields was roughly a run worse in 2017 than his ERA would indicate. His strikeout and walk rates were basically carbon copies of his 2016 marks -- the baseball Gods just decided to smile on the right-hander after frowning on him the year before (.219 BABIP, 88.1 percent strand rate in 2017, .390 BABIP, 66.8 percent strand rate in 2016). He induced more swings on pitches out of the strike zone and improved his first-pitch strike rate considerably, but hitters responded to the latter by swinging at more pitches in the zone, and they made more hard contact with pitches in the zone. Fields was a solid source of holds and he may take over primary setup duties with Brandon Morrow hitting free agency, but his appeal is limited in standard mixed leagues.

Despite a career 2.99 FIP and 11.1 K/9, Fields has struggled throughout his career to turn strong peripherals into positive results, possessing a 4.34 ERA in four MLB seasons. Fields is either one of the unluckiest players in baseball, or has a real problem with batted balls in play that is in FIP's blind spot. The Dodgers decided to take a chance on him at the 2016 trade deadline by acquiring him from the Astros and were rewarded with a 2.79 ERA in 19.1 innings, good enough to land him a playoff roster spot. Fields throws a mid-90s fastball and an inconsistent knuckle curveball, a deadly combination when they're both working. He could stand to get some late-inning opportunities for the Dodgers in 2017 if his improvement with them is real, but he doesn't have much time left to develop at age 31.

Despite opening last season on the DL due to a groin strain suffered in spring training, Fields returned in late April and immediately made an impact out of the Astros' bullpen. The third-year pro proved just how dominant he could be, compiling a 0.77 ERA with a 19:4 K:BB ratio over 11.2 innings during the month of May. He experienced a few hiccups in June and September, but finished the year with a career-best 3.55 ERA and 1.14 WHIP. Fields has a closer's repertoire (11.9 K/9 and an average fastball of 94.3 mph) and prior experience in the role (nine career saves), but he'll return to the Houston bullpen behind Ken Giles, Luke Gregerson, and Pat Neshek in the pecking order for saves.

Fields was dominant through stretches of 2014, fanning hitters at an elite 11.5 K/9 clip while significantly reducing his walk rate (2.8 BB/9) compared to the year prior. Unfortunately, there a few disastrous outings mixed in, which attributed to a lofty 4.45 ERA. An uptick in fastball velocity (94.4 mph) and a 2.16 FIP are promising signs of a potential breakout season in 2015, however, as Fields is a favorite to break camp with a bullpen spot for the Astros. Keep in mind, however, that he's further away from closing with the team's offseason additions of Luke Gregerson and Pat Neshek.

Fields, the first overall selection in the 2012 Rule 5 draft, earned a bullpen role with the Astros out of camp and went on to have an up-and-down rookie season in Houston. For the most part, his peripherals (9.5 K/9, 4.3 BB/9) were in line with his minor league ratios (10.3 K/9, 4.8 BB/9), but Fields allowed eight home runs in 38 innings for a 1.9 HR/9 mark after he permitted just 0.5 HR/9 in the minors. He will need to cut down on the number of long balls he allows as the team continues its search for a consistent and reliable closer. The 28-year-old right-hander picked up five saves for the Astros down the stretch after Jose Veras was traded and Chia-Jen Lo proved to be ineffective in his opportunities. Despite minimal experience, Fields appears likely to open the season as the Astros' closer since he has the strikeout repertoire and fastball (93.7 mph average) that is typically desired for the role.

The Mariners' No. 1 draft choice in 2008, Fields didn't sign until February 2009. The long layoff might have contributed to his struggles, and he was shut down for a bit with dead arm. Fields throws hard, and his 97-mph fastball didn't disappoint, registering a 9.7 K/9IP, but he lacked command and control, issuing 5.9 BB/9IP. Phillippe Aumont's trade to Philadelphia helps Fields' cause, though the Mariners have plenty of late-inning options should closer David Aardsma falter, so there's no need to rush Fields. He will likely begin the season in Triple-A with a callup perhaps coming in summer.