Pirates bring back the new, improved Ivan Nova

After winning 98 games in 2015 — a sum that didn’t net them the NL Central crown yet would have won any other division title — the Pirates looked to be set up for long-term prosperity. Their formidable pitching staff, along with one of the best outfields in the majors, had made them a three-year playoff team, and the streak appeared that it would extend to four seasons.

It didn’t, though. Thanks to a confluence of factors — chief among them the implosions of Francisco Liriano and Jon Niese, and the rapid aging of Andrew McCutchen — the Pirates stumbled their way to a 78-83 finish this year. And like many non-playoff teams, the Bucs sold off some of their players at the trade deadline. They shipped Liriano north of the border, giving up a few prospects to convince the Blue Jays to take on his bloated contract. They dealt closer Mark Melancon to the Nationals, receiving a few decent players in exchange for the soon-to-be-a-free-agent bullpen ace.

The Pirates did make one semi-significant acquisition, though: They gave up a couple of low-level prospects to acquire the Yankees’ Ivan Nova. At the time, my BtBS colleague Ronnie Socash noticed that, while Nova’s results had dropped off in 2016, he still looked like the same pitcher, which could help him rebound in Pittsburgh:

That optimism ultimately paid off. Over 11 starts and 64.2 innings with the Pirates, Nova cruised to a 3.06 ERA and 2.62 FIP, each of which was one of the best marks of the season’s last two months. That second-half surge encouraged Pittsburgh to bring him back, on a three-year, $26 million deal.

What made Nova so great for the Pirates, after he posted a 4.90 ERA and 5.10 FIP in his first four months with the Yankees? He started picking up some more strikeouts, but more importantly, his walks essentially vanished:

In August and September, Nova faced 263 batters. Three of them — yes, three — earned a free pass. The resulting 1.1 percent walk rate led the majors; second-place Rick Porcello, at 2.4 percent, trailed Nova by more than a percentage point. Control that exceptional, combined with some Ks and ground balls, makes for an insurmountable pitcher.

How did Nova dominate like this? The answer, on the surface, is simple: He threw 70.4 percent of his pitches for strikes — a skill that correlates to walk rate, as well as strikeout rate. But the means by which he racked up those strikes makes things a little more complicated.

Across the past two years, 126 pitchers have compiled at least 200 innings. The graph below shows their zone and O-Swing rates, with Nova’s Pittsburgh numbers inserted in red:

Most of the time, pitchers who pound the strike zone won’t get hitters to chase, usually because they don’t have great stuff (which forces them to pound the zone). On the flipside, hurlers who can make hitters offer at pitches outside the strike zone will tend to throw there more often, to gain the weak contact that’ll come from those swings.

Then there’s Nova. As a Pirate, he threw 51.2 percent of his pitches in the strike zone and got hitters to chase 38.0 percent of the time when he didn’t. Given how much he stands apart on the graph, we might wonder: Can he keep this up? If he continues to throw this many pitches in the strike zone, won’t hitters eventually catch on and stop chasing?

In 2017 and beyond, Nova’s walk rate will probably regress toward the mean; a 1.1 percent clip just isn’t sustainable long-term. Nevertheless, he should remain an above-average pitcher with this recipe. He never had this high zone/high O-Swing rate combination in New York, so maintaining anything close to it here would keep him afloat.

In Pittsburgh, Nova worked his way to an ERA 24 percent better than the NL average, with a FIP 34 percent better. Even returning to average results would make this a great deal for the Pirates — Steamer foresees a 2.4-fWAR campaign in 2017, which for $9 million is a hell of a bargain. At, say, $7 million per win, Nova needs to earn four WAR over the next three years to pay off this contract; he got halfway there in the last two months of this season, so it certainly seems likely that he’ll reach that threshold.

After playoff runs in 2013, 2014, and 2015, the Pirates fell short in 2016, but that hasn’t deterred them from trying to contend in 2017. They seem to have decided they won’t trade McCutchen, whom they’ll count on to rebound in 2017. If he does — and if Nova solidifies the rotation with his high-strike ways — the Cubs may again have some competition in the NL Central.