Phillies: The defensive impact of the J.T. Realmuto trade

A dive into the defensive numbers of J.T. Realmuto and Jorge Alfaro show that the move makes the Phillies slightly worse defensively.

The trade for J.T. Realmuto came at a surprise to many Phillies fans, probably because of how fast the whole deal came together. Now that the dust has settled, the trade can be analyzed for all its parts.

First, we know that this is a huge upgrade offensively for the Phillies, and Realmuto seems poised for a breakout which was broken down earlier this week by John Town. However, from a defensive perspective, Realmuto is a slight downgrade from Alfaro.

When looking at defensive stats for catchers, there are three things to focus on: pitch framing, blocking, and throwing. Looking at all three of these, according to Baseball Prospectus, Alfaro saved 9.3 more runs than Realmuto did last season. But taking a deeper dive into the numbers the gap is not as exaggerated as it seems.

Pitch Framing

This is where Alfaro has the biggest advantage over Realmuto. Alfaro saved 12.3 runs with his pitch framing compared to -0.4 runs saved by Realmuto. The negative number looks bad at first glance but taking into account the 117 catchers that were logged and ranked by Baseball Prospectus, Realmuto comes in slightly below league average at 71.

Meanwhile, Alfaro is an elite framer, coming in as the fifth best in the entire league behind only the likes of Yasmani Grandal, Max Stassi, Tyler Flowers, and Austin Hedges.

Blocking

Here is the part of Alfaro’s game that most fans found irritating. He ranked fourth-worst in blocking runs last season. Over the course of the season, he led the National League with ten passed balls and allowed 49 wild pitches. Bringing in Realmuto, who was 17th-best in blocking runs and allowed eight passed balls and 34 wild pitches, will be a welcome sight to those who had headaches watching the Alfaro run to the backstop.

Having a huge upgrade at blocking helps mitigate the sting from losing elite level framing. This could be an advantage for Aaron Nola, Jake Arrieta, and Nick Pivetta who sometimes spike their breaking pitches to get swings and misses.

Throwing

There is only a slight difference in the throwing ability of these two catchers, it has been well documented the cannon that Alfaro possessed behind home plate. He had the fastest average throwing velocity in the majors according to MLB Statcast at 90.8 MPH, but right behind him was Realmuto at 87.8 MPH.

Realmuto had the fastest pop time, which means the speed of getting the ball from the glove to out of his hand and thrown towards the base that is being stolen, in baseball at 1.9 seconds. Alfaro was third at 1.94.

Both threw out 21 base-stealers, with Realmuto having the significantly higher caught stealing rate at 38.2% compared to 26%. Realmuto will help keep the basepaths clean and limit runners in scoring position.

Next. Phillies Wall of Fame candidate: Placido Polanco. dark

A big priority for the Phillies in this off-season has been improving the defense, where they were abysmal last season. Getting Jean Segura and Andrew McCutchen, as well as moving Rhys Hoskins back to first base should go a long way towards these improvements. Even with losing slight defensive value that in this trade, 2019 should be a season of vast improvement on the diamond.

Home/Phillies News

Phillies: The defensive impact of the J.T. Realmuto trade

By Kevin Schaeffer | Feb 10, 2019

A dive into the defensive numbers of J.T. Realmuto and Jorge Alfaro show that the move makes the Phillies slightly worse defensively.

Pitch Framing

Blocking

More from That Balls Outta Here

Throwing