Much has been made about Javier Baez’ recent patience at the plate. Allegedly, he’s been swinging at fewer pitches outside the strike zone and that’s driving his recent strong hitting. Baez has a .938 OPS with the Mets, after having a .775 OPS the beginning of the season with the Cubs. But that doesn’t even tell the full story. In Baez’ first 19 games with the Mets, he had a .667 OPS over 73 PA. In his last 79 PA, he has a 1.180 OPS.
So, what changed? Clearly his BABIP, as he had a .244 mark in the first batch with the Mets and a .500 one in the second. But he also had 3 BB and 24 Ks in 73 PA in the first stretch, compared to 9 BB and 18 Ks in 79 PA in the second period. Everyone is going to look good when the hits are falling in like they are currently for Baez. But when you improve your K/BB ratio from 8.0 to 2.0 and your K% from 32.8% to 22.8% – that’s something besides the hits finding holes.
Let’s dig a little deeper. TexasLeaguer.com has pitch-by-pitch breakdowns for each batter every night. Along with what happened, there’s a little video showing the path of the pitch. I used this video, which had a strike zone box like the one you see in TV broadcasts, to determine if a pitch would be a ball or a strike.
I went through and looked at each PA for Baez in his first seven games as a Met, along with his last seven games. There’s nothing magical about seven games – it’s just what fit nicely in one column in my notebook. While looking at each PA, I ignored the called strikes. But each swinging strike was viewed to see if the pitch was in the strike zone or not. If any part of the ball caught a piece of the strike zone, it was counted as a strike. The following charts will have the total number of pitches, the total number of pitches that would be ruled balls – regardless if Baez swung or not – and the total number of these ruled balls at which Baez swung.
| Date | Inning | TP | Balls | Swings |
|---|---|---|---|---|
| 31-Jul | 2 | 1 | 1 | 1 |
| 31-Jul | 4 | 4 | 3 | 2 |
| 31-Jul | 6 | 4 | 3 | 2 |
| 31-Jul | 7 | 6 | 5 | 2 |
| 1-Aug | 2 | 5 | 3 | 1 |
| 1-Aug | 4 | 1 | 0 | 0 |
| 1-Aug | 6 | 5 | 3 | 1 |
| 1-Aug | 9 | 4 | 2 | 0 |
| 2-Aug | 2 | 5 | 5 | 1 |
| 2-Aug | 3 | 3 | 3 | 1 |
| 2-Aug | 5 | 3 | 2 | 2 |
| 2-Aug | 8 | 4 | 1 | 1 |
| 3-Aug | 1 | 5 | 4 | 2 |
| 3-Aug | 4 | 5 | 3 | 0 |
| 3-Aug | 6 | 3 | 1 | 1 |
| 3-Aug | 8 | 1 | 0 | 0 |
| 4-Aug | 2 | 2 | 0 | 0 |
| 4-Aug | 3 | 2 | 0 | 0 |
| 4-Aug | 6 | 6 | 5 | 2 |
| 4-Aug | 8 | 4 | 2 | 1 |
| 4-Aug | 9 | 4 | 3 | 2 |
| 5-Aug | 1 | 3 | 2 | 2 |
| 5-Aug | 4 | 5 | 3 | 2 |
| 5-Aug | 5 | 8 | 6 | 3 |
| 5-Aug | 7 | 7 | 3 | 0 |
| 5-Aug | 9 | 4 | 2 | 1 |
| 6-Aug | 2 | 6 | 3 | 0 |
| 6-Aug | 3 | 3 | 2 | 1 |
| 6-Aug | 5 | 5 | 3 | 1 |
| 6-Aug | 8 | 4 | 3 | 3 |
| Totals | 122 | 76 | 35 |
In these seven games, Baez saw 122 pitches in 30 PA, a total of 4.1 pitches per PA. Of those 122 pitches, 76 were outside of the strike zone. Stated another way, 62.3% of the pitches that were thrown to him were balls. This is taking on faith that all pitches that were called strikes were, indeed, strikes. Of the 76 pitches that were balls, Baez swung at 35 of them, or 46.1%.
Now let’s do the same chart but this time for his last seven games:
| Date | Inning | TP | Balls | Swings |
|---|---|---|---|---|
| 14-Sep | 1 | 1 | 0 | 0 |
| 14-Sep | 4 | 5 | 4 | 0 |
| 14-Sep | 6 | 7 | 5 | 1 |
| 14-Sep | 9 | 1 | 0 | 0 |
| 14-Sep | 11 | 0 | 0 | 0 |
| 15-Sep | 1 | 3 | 1 | 0 |
| 15-Sep | 3 | 3 | 2 | 0 |
| 15-Sep | 5 | 5 | 3 | 0 |
| 15-Sep | 7 | 5 | 5 | 3 |
| 15-Sep | 9 | 3 | 2 | 0 |
| 17-Sep | 2 | 5 | 4 | 1 |
| 17-Sep | 4 | 2 | 1 | 1 |
| 17-Sep | 6 | 6 | 4 | 0 |
| 17-Sep | 8 | 3 | 1 | 1 |
| 18-Sep | 2 | 4 | 1 | 0 |
| 18-Sep | 4 | 1 | 0 | 0 |
| 18-Sep | 7 | 4 | 3 | 2 |
| 18-Sep | 9 | 5 | 2 | 0 |
| 19-Sep | 1 | 5 | 4 | 2 |
| 19-Sep | 4 | 1 | 1 | 1 |
| 19-Sep | 6 | 6 | 5 | 3 |
| 19-Sep | 8 | 6 | 4 | 0 |
| 21-Sep | 1 | 2 | 2 | 2 |
| 21-Sep | 4 | 3 | 0 | 0 |
| 21-Sep | 5 | 3 | 0 | 0 |
| 21-Sep | 8 | 3 | 1 | 0 |
| 22-Sep | 2 | 4 | 4 | 0 |
| 22-Sep | 4 | 3 | 2 | 1 |
| 22-Sep | 5 | 5 | 3 | 1 |
| 104 | 64 | 19 |
The PA in the 11th inning on 9/14 was an intentional walk. That PA will be disregarded. So, in the last seven games, Baez saw 104 pitches in 28 PA for a total of 3.7 pitchers per PA. Of those 104 pitches, 64 were outside of the strike zone. Stated another way, 61.5% of the pitches that were thrown to him were balls. This is, again, taking on faith that all pitches that were called strikes were, indeed, strikes. Of the 64 pitches that were balls, Baez swung at 19 of them, or 29.7%.
Pitchers haven’t seemingly adjusted to Baez yet. In the first group they threw him balls 62.3% of the time and in the second group that was virtually unchanged at 61.5%. But we see a big difference in the number of swings at balls by Baez, as he’s gone from 46.1% to 29.7%.
At FanGraphs we can check the leaderboards for swings on pitches outside the strike zone, labeled O-Swing%. Among qualified hitters, the worst O-Swing% this year belongs to Salvador Perez, with a 48.3 rate. For the year, Baez ranks third with a 46.4 mark. There are 134 hitters who qualify for the leaderboards. If Baez was able to keep up his 29.7% mark of the past seven games, he would be tied for 55th in this category. He would go from being the third-worst to being in the top 40% of all qualified hitters.
Of course, results of seven games are hardly anything upon which to make a judgment.
Having said that, Baez’ improved plate discipline is likely much more than seven games. But whatever point the idea took hold is unlikely to be large enough to convince everyone. And that’s ok. This is certainly a case where reasonable people can disagree.
We’ll have a few more games this year to watch Baez, to see if this improved plate discipline holds. Again, probably not enough to convince everyone but if we end up with 40-50 games – somewhere in the neighborhood of 190 PA of this improved discipline – that’s not insignificant.
Several years ago, statistician Russell Carleton, who later worked for the Mets in 2019, calculated the total number of PA you need for a given statistic to reach the point where the correlation between that sample and another sample of the same size is 0.7 (i.e. R^2 of .49). That came to be popularly known as the point of “stabilization,” a term that Carleton didn’t like. He calculated this for numerous stats and the stabilization point is all over the map. It takes 290 PA for your rate of hitting singles to stabilize while it takes 460 PA for OBP to stabilize.
Carleton found the stabilization point for walks to be 120 PA and strikeouts to be 60 – the two lowest points there are. We can compare 120 PA with the Cubs versus the last 120 PA of the season for Baez once the season is over to compare his walks and strikeouts to see how the rates compare.
Very dramatic changes short term! Thanks for taking the time to do this analysis, Brian!
Baez may be stubborn, but I don’t think he’s stupid enough to go back to his wild-swinging ways. He must see the results of his new approach!
Even this year, with lots of Ks with the Cubs and Mets, he’s at 5 WAR. If he can have a doable 6 WAR year next year, that’s worth about $48 million or so. Giving him a 5 year/$125 million deal sounds reasonable.
I, too, have changed my mind about him. I think he can handle NYC, can be a team leader, and his energy will rub off on some of the Mets players.
The “energy” aspect is very important.
I’m skeptical that Baez has seen the light ( or in this case the strike zone). His character is questionable. He is though, the best second base free agent out there and with no draft compensation. If he were signed the Mets would be better. If Cohen wants to turned this team around fast then Baez signing ( along with others) is the quickest way.