Anthony Rizzo: The making of an All-Star

Thanks to the desires of the fans’ Final Vote, Chicago Cubs first baseman Anthony Rizzo was an All-Star, and a well-deserved one at that. The towering lefty has crushed the ball this season to the tune of a .275/.381/.499 line, combining power and plate discipline with solid defense and decent base running. Rizzo is the rare prospect who has become the player he was supposed to be, but it all happened a year too late.

Rizzo was called up to the majors for his first extended action in 2012, and put together an exceptional rookie year across 368 plate appearances (PA). All of the tools Rizzo has now were on display that year, albeit in a slightly reduced fashion: Solid contact skills, the patience to take a base on balls when necessary, and the power to punish pitchers for their mistakes. As a 22-year-old rookie, Rizzo was putting up stats like an average major-league first baseman, and so it was natural to expect that he was primed for a breakout as he gathered some more experience.

2013 should have been Rizzo’s breakout year. But things didn’t come together that way: His average fell by 50 points, and even though his walk rates and defense improved, it wasn’t nearly enough to counteract the drop in productivity from the bat. The standard explanation which analysts pointed to was an unsustainably low batting average on balls in play (BABIP). Rizzo’s BABIP last year was .258, good for 249th out of 276 hitters with more than 300 PAs. BABIP is notoriously random and slow to stabilize, so it was reasonable to assume that Rizzo was just getting unlucky.

By the same token, one might believe that maybe Rizzo’s luck has turned this season: His BABIP is back to a more potent (but still below-average) .298. Moreover, there’s nothing obviously altered in his plate discipline profile. However, as the adage goes: There’s lies, damned lies, and statistics. A closer examination reveals that Rizzo has altered his approach in several ways.

Rizzo’s plate discipline profile speaks to both a good eye for the strike zone and some patience. Despite seeing only about 45 percent of his pitches in the strike zone, Rizzo has maintained a low swing rate of 43 percent, solidly middle of the pack (53rd lowest) in MLB. Rizzo is not an undisciplined hacker, nor was he last year, when his swing rate was 45 percent. Even though his tendency to swing has gone down, it hardly seems enough to explain the difference in results between this season and last.

That slight difference in plate discipline conceals a significant modification of Rizzo’s approach. Consider what happens when breaking down Rizzo’s swing rate by count.

While Rizzo’s overall swing rate seems basically unchanged, his swing rate on a given count has been substantially more dynamic. The reason that this variation doesn’t show up in the overall swing rate is that some of it is offsetting: Rizzo increased his swing rate on 2-1 counts nearly as much as he decreased it on 2-2 counts, and all of these differences together lead to a net change of very little.

Aggregating Rizzo’s swing rates in this way displays a calculated pattern. Examining the swing rate by the number of pitches in a count, it becomes obvious that Rizzo has become more selective specifically early in the count.

Rizzo’s swing rate is down by 8 percent and 6 percent in the first two pitches of every at-bat, but up after that. It drops again late in the count, perhaps signaling an increased willingness to take a walk when necessary. The pronounced drop early in the count allows Rizzo to get deeper into each plate appearance, in effect not giving away strikes early on.

The difference in approach has had a positive effect on his pitches per plate appearance. Last season, Rizzo possessed a rather pedestrian mark of 3.79 pitches/PA, good for 37th in the NL. This year, Rizzo has increased to 4.03 pitches/PA, pushing him to 17th in the NL. The number of pitches per plate appearance is especially important for an intimidating slugger, because each additional throw represents one more chance for a pitcher to make a mistake upon which Rizzo can capitalize. His swing profile this year, although not overtly distinct from last year, has driven him to march into deeper counts and get more opportunities to see hittable pitches.

Another crucial dimension is where Rizzo swings. The batter cannot control where a pitcher chooses to pitch him, but he can choose which balls he swings at. Knowing then which pitches to hit and which to let by is a crucial skill for any hitter.

Last season, Rizzo had a serious problem with infield flyballs, putting almost 10 percent of his balls in play into that unfortunate category. Infield flyballs result predominantly from weak contact high in the strike zone. Essentially, the batter swings below a pitch, rolling under it and causing it to pop up into an easy out. Rizzo is especially vulnerable to the infield fly because of his uppercut swing.

It was therefore imperative that Rizzo learn to let the high fastballs pass. Last year, by Pitchf/x metrics, Rizzo swung at pitches on average 2.49 feet above the ground. That’s significantly above the league-wide mark of 2.37 feet, but then again, Rizzo is tall and his strike zone is higher, too. Still, Rizzo had a predilection for swinging at pitches way too far up in the zone. A unaceptable 2.3 percent of Rizzo’s cuts came at pitches higher than 4 feet. Compared to the MLB average of 0.8 percent, that’s way too high (and inexplicable by Rizzo’s stature alone).

This year, Rizzo’s swings tell an unfamiliar story. In 2014, his swings have been at pitches an average of 2.34 feet off the ground. The difference in the average height of pitches at which Rizzo has swung between last year and this year is 1.8 inches, which might not seem like much until realizing that this difference has come over more than 500 swings so far this season.

Multiplied by so many swings, an average difference of an inch or two can amount to a serious increase in quality contact. That, in turn, manifests as a threefold decrease in infield-fly rates (from 9.9 percent last year to 3.3 percent this year) and an increase in line drives (2013: 23.9 percent; 2014: 27.1 percent). These are small differences individually, but they speak to an improved pitch recognition skill, which translates into better-struck pitches. Because of Rizzo’s unique attributes, it’s vital that he learns which pitches are best to put into play, and he seems to have taken a step in that direction between years.

Finally, another of the major reasons Rizzo suffered last year was an astounding deficiency in his groundball BABIP. Some of that was likely brought on by the rise of the infield shift. As a relatively slow left-hander with strong pull tendencies, Rizzo is the classic candidate for the shift, and there’s no question that he will never manage a high groundball BABIP.

But that doesn’t mean Rizzo’s going to take the shift lying down. This year, Rizzo has attacked the shift by bunting down the left-field line, to the spot where the third basemen would be if he wasn’t shifting. For a hitter best known for his walks and moonshots, Rizzo manages to consistently lay down a solid bunt (see the link for an example). So far this season, Rizzo has tried five separate bunts (and threatened a handful of other times), collecting a trio of hits in the process.

Three bunt hits is a nice bonus to Rizzo’s season line, but of little significance. The greater value of Rizzo’s bunts is that they force the defensive alignment to change, as Chris Mosch has noted. Other teams still shift against Rizzo, and will continue to do so, but in addition to legging out a handful of extra hits, Rizzo has planted the seed of one more thing that the defense must worry about. It’s too early to analyze the bunt effect rigorously, but the threat of a bunt is enough to give Rizzo’s groundball BABIP a boost.

The Making of an All-Star

There are two lessons that stick out about Rizzo’s breakout. The first concerns BABIP. It’s known that very low and very high BABIPs are unsustainable across multiple years, such that if a given batter’s BABIP is low in Year One, it’s likely to come back up to a more average number in Year Two (otherwise known as regression to the mean). That same pattern played out for Rizzo, but it’s not as though Rizzo didn’t have something to do with it. Rizzo made a clear adjustment to his swing tendencies, waiting later in the count to attack lower pitches on average, and it is plausible that the adjustment had something to do with Rizzo’s higher BABIP. In other words, Rizzo’s change in BABIP might not have been just the product of luck but rather a considered refinement of his approach.

Second, Rizzo showcases the value of adaptability. Rizzo, like plenty of other former top prospects, has all of the physical tools to succeed, including one of the sweetest swings in the majors. But that doesn’t mean he’s predestined for success or invulnerable to the counter-adjustments of pitchers. After a bad season, Rizzo systematically identified his weaknesses and took steps to correct them, demonstrating a level of craftsmanship befitting a veteran. For the hefty lefty to make the jump from average to All-Star, he had to become smarter and savvier about when and where he put that swing to work. Something about that adaptability says that this won’t be the last time he’ll be playing in an All-Star Game.

Rob Arthur is a contributor to Baseball Prospectus.