Mike Napoli: 3 weeks and True Outcomes

With his grand slam on Saturday and another big game on Sunday, Mike Napoli bumped his team-leading RBI total up to 45 and he sits just behind David Ortiz for the team lead in home runs with nine. He is also second on the team in Fangraph’s version of wins above replacement with 1.5 trailing only Dustin Pedroia and his .500 slugging percentage is second to Ortiz. Napoli’s weighted Runs Created Plus (wRC+) is fifth among American League first basemen. With two months on the books now, Napoli has been one of the key differences in a Red Sox team that has gone from a last place finish in the AL East last season, to a division-leading 35-23.

The production from Napoli has been extremely important to the Red Sox, but it has not come without some reasons for concern. The 31-year-old slugger has the highest strikeout rate of his career, at an eye-catching 34 percent, while his walk rate is more than two percentage points off his career norm and the lowest it has been since 2010 when he was with the Angels. Despite this, his .274/.350/.502 line is still very good, but when it comes with a .397 batting average on balls in play, there is some cause to question its sustainability. Just a few games back, it appeared that cruel regression might be rearing its ugly head.

For a two week stretch in mid-May, Mike Napoli was struggling badly. He went without a home run for 52 straight plate appearances from May 14-26, hitting .214 in that span with just one extra base hit, for a slugging percentage of .238. He also struck out 20 times. Then, finally, mercifully, Napoli finally found the outfield seats on May 27 at home against the Phillies, going 2-4 with a homer, a double and walk. This one strong game didn’t immediately end Napoli’s struggles -- he has struck out eight times over the past week- but it does seem that that game signaled a change from the previous weeks.

Mike Napoli has always tended toward being a Three True Outcome type hitter. In his career, 43 percent of his plate appearances have resulted in a strikeout, a walk or a home run. He might be becoming even more prone to those outcomes as he ages. This season, 47 percent of his plate appearances have produced one of those three outcomes. That is nothing compared to TTO heroes like Rob Deer or Russell Branyan at their TTO-ing prime, but it does tell us something important about Mike Napoli as a hitter. He isn’t a player you can depend on for a high batting average, but when his bat does find the ball, he can crush it. This is not a major revelation, but it is important to keep in mind when looking at what has been happening over the last three weeks.

While the usual caveats of small sample sizes certainly apply here, Napoli’s struggles in mid-May do show us something about him as a player, as does his resurgence last week. Here are the results of his plate appearances during that rough 52-plate appearance stretch care of Texas Leaguers:

The first important piece of information here is that Napoli had very few batted balls during that stretch. With 10 walks and 20 strikeouts in 52 plate appearances, we are left with just 22 balls in play. Of course, given his propensity toward the three-true outcomes, this is actually a fairly normal number of balls in play for Napoli, it is just that we are missing around three home runs if we simply go by career rates. Still, as bad as things were, Napoli was still successful when he actually made contact. His nine total hits give him a batting average on balls in play of .409. We can’t take what occurs in a sample of just 22 balls as predictive of much, but the spray chart shows that these batted balls were not entirely random.

Generally speaking, Napoli hits a large number of his singles to left field and makes the bulk of his ground ball outs to third and short. He is missing power here, obviously, but he is quite severely restricted to one side of the field. Historically, Napoli has not been an extreme pull hitter and a spike in pulling the ball is often a sign that he is also putting the ball on the ground too much, just as we see above.

The contrast, in the week that begins with his breakout game against the Phillies is almost absurd:

That is two opposite field home runs and two opposite field doubles, a total of five hits going the other way, with just two hits to the pull side. No one should leave this site thinking the moral is Napoli-pulling-equals-bad or that hitters need to go the other way. That is not it. However, the extremes above between a set of 52 trips to the plate and other set of 23, paints a nice picture of how player’s production ebbs and flows between the many parts of that player’s game. Two weeks of batting the ball into the ground followed by a week of crushing it over the head of the right fielder eventually becomes something like this to gives us a far more complete view of one Mr. Mike Napoli.

The second important thing to note about Napoli’s two-week power outage is that his walk rate was fairly ridiculous during this time, at over 19 percent. Combined with his elevated strike out rate, it is almost as if the man just stopped swinging. During an extremely productive month of April, Napoli walked just 5.4 percent of the time, a surprisingly low rate for a man with a career rate nearing 12 percent. In May, that rate jumped way up over 13 percent, with this powerless stretch accounting for the majority of that change.

These types of extremes are nothing new for Napoli. Since 2009, the first season in which he topped 400 plate appearances, Napoli has had a walk rate below six percent over a month’s time six different times and a rate of 15 percent four times. Even with walk rates being one of the more quickly stabilizing statistics. Such small samples are prone to those types of variation but Napoli does appear to be unusually streaky with his free passes.

After beginning the season being uncharacteristically aggressive at the plate, Napoli suddenly became overly conservative with his swings as pitchers started giving him less to hit. The results of this shift were extreme, he struck out and he walked and did little else for nearly two weeks. In these last 23 plate appearances, however, Napoli is swinging again and hitting again with a .417/.462/.750 line despite a 38.5 percent punch out rate and a walk rate that has returned to earth at 7.7 percent as pitchers have returned to the zone.

This is the dilemma for the pitcher who finds himself on the hill against a Three True Outcome type like Mike Napoli. You can strike him out, so it pays to be aggressive and attack the zone. On the other hand, making a mistake is more costly than it might be against a less powerful player, so you can’t simply groove it in there. Of course, if you don’t attack the zone, the TTO player will simply sneer at your non-strike offerings. With that tightrope to walk it is easy to see how a player like Napoli would be streakier than the average hitter. When things are going well, a pitcher’s natural response would be to give the man less to hit and after his strong start to the season, that is just what they did to Napoli. It worked some -- he struck out a lot. It failed some too -- he walked at more double the league rate -- but overall, thanks to the lack of home runs, it gave the impression that this was a guy who was struggling; this was a guy you could get out. With Napoli looking less intimidating, pitchers attacked the zone again, chasing those Ks, and Napoli started swinging and started hitting again.

To some degree, Napoli’s struggles in mid-May were simply a matter of a few strikeouts where home runs might have been. In most other respects, Napoli was doing the things that he typically does. Being so prone to just three results for a plate appearance exaggerates the degree to which he may be hot or struggling at any given time. Without a couple of home runs here and there, the volume of strike outs and walks can make watching Napoli difficult. Conversely, when those home runs come in close succession, he can look better than he really is for a short stretch. These past three weeks have given us extremes of both, and combined, they illustrate his strengths and weaknesses almost perfectly.

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