Eddie Rosario is starting to turn things around in September

Oct 4, 2022 - 4:00 PM

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Eddie Rosario has, for the most part, seemed to be a disappointment for the Atlanta Braves this season. His slash line has left little to be desired with a .219/.270/.342, which has equated to a wRC+ of 69 (31 percent below league average). As far as fWAR goes, which is an accumulate stat, it shows that regardless of his plate appearances, he has added negative value. On the season, Rosario has a -1.1 fWAR. With 216 of his 265 at bats (at the time of this writing) being after his return from his eye issue, you would be hard pressed to blame most of his negative fWAR on his injury alone.

Rosario’s wOBA has also been well below league average as well. His 2022 .269 wOBA is much lower than the MLB average of .316. His expectancy stats aren’t doing him any favors either. In fact, his xwOBA is even lower at .258, where the MLB average is .309.

Eddie Rosario has adjusted to not being dreadful in September yet again

Many fans will remember how Eddie Rosario came alive at the end of the year in 2021 and carried it over into the playoffs. In 2021, Rosario’s xwOBA never went above .315 before August. Since then, he took it to a new level. In August he had an xwOBA of .366, then an xwOBA of .382 to finish out the year. For reference, if he would have had a wOBA of .382, he would have been 10^th in all of MLB in that time frame, just beating out Austin Riley.

Rosario has not been quite as impressive this year in terms of turning things around, but he has yet again started to hit much better in September after having dreadful performances for most of the rest of the season.

As can be seen in the graphic above, Rosario never had an xwOBA above .257 prior to September this year. The interesting part is that every single month that he played, his xwOBA got better. A .319 xwOBA is not mind blowing, but is respectable, considering the previously mentioned league average. His on field results have actually been much better, with a wOBA of .354, and a wRC+ of 127 for the month of September. A 127 wRC+ would place Eddie Rosario 49^th in all of MLB in that time frame.

Why has Rosario seemed to turn things around?

It is pretty obvious that early in the season Rosario’s eye issue was causing him to perform poorly, and that definitely plays a part, but it is not like he came back from injury setting the world on fire either. Rosario came back from injury on July 4^th and during that month had an xwOBA of .232 and a wRC+ of 66. To be fair, there was probably an adjustment time, but these numbers were not striking confidence by any means.

Rosario, for most of his career, has had fared much better against righties than lefties, having a wRC+ ranging from 106 to 136 during his 2018-2021 campaigns against righties, while never having a wRC+ over 99 since 2015 against lefties. So, it was concerning seeing him hit to a 76 wRC+ against righties from July-August this year, after his eyes had presumably been healed.

To get to the overall wRC+ of 127 that Rosario has held in September, something had to have changed, and it has. There are a few “smoking guns”, if you will, that point to how Eddie Rosario has been able to turn his output around in the month of September.

His wRC+ is currently sitting at 131 against righties in September pointing to an adjustment in that arena leading to positive overall production.

First, we can look at Rosario’s swing and miss percentages for the entire season. His swing and miss percentage are the highest of his career for fastballs, breaking pitches, and off speed pitches at 27.8 percent, 36.4 percent, and 33.3 percent respectively.

In the month of September, it has been a completely different story on Rosario swinging and missing than it has for the entire season. Looking at the chart below, we can see without even getting specific numbers that his swing and misses have plummeted. His swing and miss percentage has dropped on fastballs, breaking pitches, and off speed pitches to 26.4, 20.6, and 21.7 respectively. These numbers are much closer to Rosario’s “norm”.

Interestingly, in September Rosario has seen his chase rate be the highest of any month this year on fastballs and off speed pitches, and second highest of any month on breaking pitches. However, that has not seemed deter him. His swing and miss rate of pitches outside the strike zone have plummeted to the lowest of the year for him against both breaking pitches and off speed pitches. In other words, even though he’s whiffing less than before, it isn’t because he’s being more selective.

It is a very similar story against pitches inside the strike zone as well. In July and August, Rosario swung and missed on 35.3 percent and 32 percent of the time respectively on breaking pitches and off speed pitches inside the strike zone. In September, his swing and miss rate inside the zone has dropped down to 10.5 percent of the time on breaking pitches. Off speed pitches have not seen as much a drastic drop, but he is only swinging and missing on 12.5 percent of them in August and September after his rate being 18.2 percent in July.

One other area that has helped Rosario have more success in September is his batted ball profile. There has been a significant shift where and how Rosario has hit the ball. Prior to September this year, he was not spreading the ball well. He was pulling the ball 46.6 percent of the time and going opposite field 14.3. The placement of the hits in and of itself is not necessarily a bad thing. However, during that time frame he was hitting line drives just 18.8 percent of the time, while hitting grounders 40.6 percent of the time.

Since the start of September, Rosario has started to spread the ball across the field more. He is pulling the ball 31.1 percent of the time, while going opposite field 22.2 percent of the time. If you do the math, that means he is hitting the ball up the middle a whopping 46.7 percent of the time. Combine this with him now hitting line drives at a much better rate of 25.6 percent of the time, and his grounder rate being down to 32.6 percent of the time, and it is a pretty obvious that his batted ball profile is a big reason he is being more productive. Interestingly, his hard hit rate and soft hit rate has not changed much, both changing less than 3 percent of the time, showing it seems to be more about hit type and placement more than hitting the ball harder.

Recap

It has been fun watching Rosario yet again turn things around September. Rosario seems to have invested in changing his approach and it has been paying great dividends:

• Against righties, Rosario has lowered his swing and miss percentages as a whole on all pitch types
• On off speed and breaking pitches against righties, his swing and miss percentage of pitches outside the zone has plummeted
• Rosario is making contact on breaking pitches and off speed pitches inside the strike zone at a much higher rate
• While hitting more line drives and less groundballs, Rosario is also spreading the ball around the field better as well.