Didi Gregorius, who will play 2018 in his age-28 season, has improved his performance year after year since coming to New York from Arizona. Not only is Gregorius demonstrating All-Star ability on the field, he has become one of the key members in the clubhouse.
In 2017, Gregorius set career highs with a .287 batting average, .478 slugging percentage, .796 OPS, 106 OPS+, 25 home runs, and 87 RBI. The impressive part to the improving counting stats is that Gregorius reached the measures in 17 fewer games and 27 fewer plate appearances than 2016. Due in part to extenuating circumstances with the rest of the lineup, Gregorius often hit cleanup in 2017.
In the field, Gregorius improved in the area of advanced defensive metrics, posting a +1 in defensive runs saved, which was much improved from his -9 mark in 2016. He has decent enough range, but whether of his own choosing or his coaches, he was often placed out of position, which prevented him from getting to some ground balls hit in his vicinity. Regardless, Gregorius continues to possess one of the stronger arms in the game from the shortstop position.
Besides last season, Gregorius has proven to be a durable player. The time Gregorius missed in 2017 resulted from a right shoulder injury suffered during the World Baseball Classic. Without indicting the WBC as the reason for all early-season injuries, there is some truth to the fact that the players are put into strenuous game situations much earlier than in a normal season. Gregorius will not have to worry about this in 2018, and he demonstrated the injury was behind him with his strong performance.
The questions about Gregorius are no longer about the proposition of filling in an icon's shoes, but rather center on whether can he continue to outdistance his previous season's production.
Gregorius enters the 2018 season in the prime of his career, so theoretically he may not have reached his production ceiling. He would seemingly have the benefit of an even deeper group of hitters around him in 2018, as well as having one more season under his belt in which he's not trying to prove himself.
While it seemed that Gregorius was flourishing as the cleanup hitter, he managed just an 88 OPS+ in the spot, and actually performed better out of the fifth, sixth and seventh slots (102 OPS+, 112 OPS+ and 129 OPS+ respectively) in the batting order. Considering the addition of Giancarlo Stanton and a healthy Greg Bird, Gregorius could be back in a more comfortable and fitting spot in the lineup.
Gregorius does not draw or care to draw walks, so his on-base percentage will always be heavily dependent on his batting average to come close to league average. Asking or expecting this characteristic to change is unrealistic.
Another aspect to keep an eye on with Gregorius involves his batting splits. He flourished against right-handed pitchers (.848 OPS, 116 OPS+), while he skidded against left-handers (.646 OPS, 92 OPS+) in 2017. Gregorius excelled against lefties in 2016, generating strong reverse-splits which were contrary to the results of any previous season. It will be interesting to see if his 2016 splits remain the outlier.
Surprisingly, Gregorius was unable to take full advantage of Yankee Stadium last season (.707 OPS, 82 OPS+), while thriving on the road (.882 OPS, 139 OPS+). As with his lefty/righty splits, the inverse was true in 2016. It seems that if Gregorius is going to improve upon his overall 2017 statistics, he will need to close the gap between his righty/lefty splits as well as the performance at Yankee Stadium with road ballparks.
On the positive side of the advanced metrics, Gregorius decreased his strikeout percentage (12.3 percent) for the third straight season. Next, Gregorius produced a 9.1 percent rate in garnering extra-base hits among plate appearances for the second straight season (six-year MLB average is 7.7 percent).
There may be some regression with Gregorius, but expecting a .280/.315/.450 slash line with 50 extra-base hits, 20-plus home runs and 80 or more RBI is well within reason.
Gregorius has apparently figured out how to maximize his performance, turning himself into a player with a chance to be an All-Star performer this season. As in 2017, his production on both sides of the ball will be extremely important to the success of this season's club.