Can Mike Zunino finally stick?

The Mariners are in something of a strange place right now. With Robinson Cano, Nelson Cruz, and Kyle Seager in the fold, their core of position players is one of the strongest in the majors. Still, those players are getting old, and the rotation probably won’t give them much help, either. As with the Tigers, the Mariners’ stars should make them a decent team in 2017, but they’ll need some help from the supporting cast.

Mike Zunino is no one’s idea of a star. He fields well, sure — over the 2,914 innings he’s caught for Seattle, he’s earned 38.5 framing runs according to Baseball Prospectus. But his performance at the plate has always kept him down: As a big-leaguer, he’s hit a measly .195/.262/.370, which translates to a 78 wRC+.

That aggregate figure belies a recent improvement, though. In a brief showing last year, Zunino actually hit pretty well for himself; his .207/.318/.470 triple-slash translated to a 115 wRC+. Thanks to that comparatively hot hitting, he was worth 1.2 fWAR in a mere 192 plate appearances. Over a full season, that production (which, crucially, doesn’t include framing) would make him a three- to four-win player — exactly what the Mariners need to make it to the next level.

The big alarm bell — BABIP — that typically sounds with small-sample breakouts won’t go off here. Zunino had a .250 BABIP last year, in line with his .249 career mark. Likewise, he struck out even more often in 2016 (33.9 percent) than he did from 2013-2015 (32.1 percent). Zunino’s step forward came because of two things: power and walks.

We’ll discuss Zunino’s ISO in a moment, but I want to narrow in on his free passes, because they seem a mite more sustainable. After walking in 5.1 percent of his plate appearances during his first three years in the majors, Zunino more than doubled that in his fourth year, walking at a 10.9 percent clip. His patience during 2016 was nothing unprecedented:

Image via FanGraphs

Zunino had a similar stretch during the second half of 2015 — a period where he notched a 3.7 percent walk rate. So what changed during his 2016 trial? How did he accumulate all those bases on balls?

Image via FanGraphs

Simple: He developed his plate discipline. While Zunino continued to swing at strikes — his 68.6 percent Z-Swing rate was exactly the same as his career average — he trimmed his O-Swing rate from 35.4 percent to 27.7 percent. That’s a massive improvement, which explains the more than 200 percent rise in walk rate, and which should keep on paying dividends going forward.

Because Zunino made much less contact in 2016 (64.9 percent) than he did in the years before it (67.6 percent), his swinging-strike rate — and, as mentioned previously, his strikeout rate — remained elevated. That progress with pitch judgment nevertheless did him a lot of good, and if his clout starts to fade, it could cushion his fall.

On that note: Zunino’s power gave him a boost last year — his .262 ISO was more than a hundred points above the .160 he tallied from 2013-15. As someone who rarely puts the ball on the ground, he’ll naturally rack up the home runs, but a 23.1 percent home run/fly ball rate seems unlikely to recur. Zunino made hard contact on 40.4 percent of his flies last year, which wasn’t much higher than the big-league average of 38.6 percent.

Still, the walks should help. If he continues to frame like a god — which, given the volatile nature of framing, might not happen — Zunino won’t need to crush at the plate. Hell, the average MLB catcher had an 87 wRC+ in 2016; anything above that would be gravy in the Mariners’ book. After the team rushed him to the bigs in 2013, Zunino took some time in the minors to cool off last year, and the results suggest he might have turned a corner.

FanGraphs currently projects Seattle to go 83-79, behind Houston in the AL West yet within reach of a Wild Card spot. For the club to break its postseason drought, Cano, Cruz, and Seager will have to drive in a whole ton of runs; for them to do that, someone has reached base ahead of them. Zunino’s improved plate discipline could make him the perfect sidekick to that tremendous trio.

Ryan Romano is the co-managing editor for Beyond the Box Score. He also writes about the Orioles for Camden Depot, sometimes. Follow him on Twitter if you enjoy angry tweets about Maryland sports.