Steady Mercer brings stability to shortstop

With Spring Training approaching, it's time for an in-depth look at the Pirates' roster. This is the fourth part of a series checking in on their current and future options at each position. Next up: shortstop.
Big question: How far off is the future?
There is no question the starting shortstop job belongs to Jordy Mercer. The issue is what comes next. Mercer will earn $6.75 million in his final season of arbitration-eligibility, then the 31-year-old can become a free agent. Coincidentally, the Pirates have a ton of shortstop talent and depth in their farm system.
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So, will Mercer pass the torch to Kevin Newman this summer or next year? Will Newman be ready? Keep in mind Cole Tucker is not far behind Newman, so for all the stability Mercer has brought -- this will be his fifth Opening Day start at shortstop -- there's going to be some turnover soon.
The starter: Mercer
"Steady" might best describe Mercer. His production last season was about the same as it was in 2016, as he put up a .255/.326/.406 line with a career-high 14 homers in 145 games. His 88 wRC+ was identical to his 2016 output. Most advanced metrics indicated Mercer's defense was better last year than in '16.
The only thing that changed last year was Mercer's typical production against left-handers; he posted a .723 OPS in 135 plate appearances, below his career .824 mark. He was at his best batting eighth, recording a .284/.375/.462 line from that spot.

Backing up: Sean Rodríguez, Max Moroff
Neither will unseat Mercer, who started 143 games last season. Moroff made 10 starts there, Rodriguez picked up six, two went to Gift Ngoepe (now a Blue Jay) and Adam Frazier started once.
Frazier could be listed here, but he currently looks like part of their outfield mix and a potential second-base option if Josh Harrison is traded. Moroff may be their next-best defensive option behind Mercer. In only 295 2/3 innings, Moroff totaled 5 DRS between second, third and short. Rodriguez may not be flashy, but he can and will play everywhere.

Depth: Newman
After his time in big league Spring Training, Newman will start the season back in Triple-A Indianapolis, where he put up a .283/.314/.373 line with no homers and seven steals in 40 games. It seems like just a matter of time until the 2015 first-round Draft pick is called up, but he'll have to prove himself against Triple-A pitching first.
Newman, 24, is regarded as a strong contact hitter, but his 9.9 percent strikeout rate in the Minors is paired with a similarly small 7 percent walk rate. He probably won't match Mercer's power, either, as he's hit 11 home runs in 285 professional games. Like Mercer, Newman is considered a solid (perhaps unspectacular) defender.

In the pipeline
The Pirates are deep in shortstop prospects, starting with Newman in Triple-A. He could be bumped to second base or a utility role by Tucker, the Pirates' first-round pick in 2014, whenever they're both ready for the Majors.
Tucker, a 21-year-old switch-hitter, posted a .275/.358/.408 line with six homers and 47 steals between Class A Advanced Bradenton and Double-A Altoona, where he should return to start this season. Tucker is younger, considered to be the better defender and more productive on the bases, so there could be a legitimate shortstop competition this time next year.
Below them are Stephen Alemais, an outstanding defender who put up a .799 OPS after a midseason promotion to Bradenton, and Adrian Valerio, a glove-first shortstop who broke out with the bat by slugging 11 homers for Class A West Virginia.