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Inside the Mets' Extraordinary Improvement on Defense

The Mets are in first place despite a disappointing offense and an MLB-high 17 players on the injured list, largely thanks to a massive turnaround on defense.

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If you wonder how the New York Mets could possibly be in first place with an MLB-high 17 players on the injured list, the answer can be found in a .191 hitter, two Ivy League math whizzes who were still in college in 2015, and the best pitcher on the planet who is learning to love baseball’s new math.

The Mets have pulled off a stunning transformation on defense. After four straight seasons wasting elite arms with a bottom five defense, the Mets are a top-four defensive team. They have done so by beefing up their analytics department, using more than twice as many shifts as they did last year, and by relying on human connection to get players to buy into cold, hard data. It is a modern baseball success story of marrying information with performance.

When asked by SI what was behind New York’s increase use of shifts and the positive impact of them, Mets president Sandy Alderson gives three reasons:

1. “We are more comfortable with the data and how we are interpreting it.”

2. “Buy in from manager and staff and expansion of traveling analysts, leading to better player buy-in.”

3. “Emphasis coming from the front office in a collaborative way.”

Asked the same question, manager Luis Rojas says, “First I have to start with two people.” He mentioned research and development analysts Jared Faust and Ben Zauzmer. He also mentioned how well the shifts have worked.

“It’s been more successful,” Rojas said, “and that’s why the whole group is trusting it more.”

New York Mets left fielder Dominic Smith (left) and right fielder Khalil Lee (26) leap in celebration after defeating the Colorado Rockies at Citi Field.

From 2017-20, no team averaged a higher fastball velocity than the Mets (93.9 mph). Yet despite those big arms the Mets in each of those seasons finished in third or fourth place and at least nine games out of first. Defense was a big problem. Starting in 2017, the Mets ranked 30th, 27th, 28th and 26th in defensive runs saved. That is why how the Mets are playing baseball this year is, as Casey Stengel would have said, an amazing story.

This is a story about more than math. But let’s begin with the math. In simple terms, here is the massive improvement by the Mets’ defense. Their MLB rank in each category is presented in parentheses:

*Line drives & groundballs

Mets Defense20202021


20.9% (27)

56.0% (2)

Defensive Runs Saved

-22 (26)

24 (4)

Defensive Efficiency

.668 (27)

.699 (13)


.317 (27)

.288 (15)


.400 (27)

.354 (16)

How did the Mets’ D get here? Follow the timeline:

March 2019: The Mets hire Faust as an R&D analyst.

Faust is less than one year out of the University of Pennsylvania, where he majored in economics with a minor in statistics before taking a job with the Yankees as a quantitative analyst.

Nov. 6, 2020: Steve Cohen purchases the Mets from the Wilpon family.

Cohen, a hedge fund manager, gives Alderson the green light to boost the team’s research and development department.

Nov. 11, 2020: Pitcher Marcus Stroman accepts the Mets’ one-year, $18.9 million qualifying offer.

Stroman is one of the most extreme groundball pitchers in baseball. Infield defense is crucial behind him. In the 11 games Stroman pitched for the Mets in 2019, batters hit .342 on balls in play against him—43 points higher than when he pitched his first 21 starts that year for Toronto. Stroman is only a good investment with a good defense.

Nov. 18, 2020: Robinson Cano is banned for the 2021 season because of PED use.

Last season Cano posted a -4 DRS at second base at age 37. Since 1934, only three second basemen played 130 games at the position at age 38 or older: Frank White in 1989, Craig Biggio in 2005 and Jeff Kent in 2007. Only White was an above average defender at the age. Replacing Cano with 29-year-old Jeff McNeil, a plus defender, was an upgrade.

Jan. 7, 2021: The Mets trade for Francisco Lindor from Cleveland.

Lindor is among the two or three best defensive shortstops in the game. Though he was hitting .191 entering Sunday, he has continued his elite defense, which is a major upgrade on Amed Rosario, who lacked range and the footwork to make backhand plays.

Lindor has an uncanny knack of reading hitters, which adds to his tremendous range that is helped by playing one of the deeper shortstop positions in the game. In non-shifts, Lindor plays four feet deeper than Rosario did and six feet deeper than Andres Gimenez, who split the job with Rosario last year.

“It’s no knock on Rosario. He was great for us,” Rojas says. “Lindor is just a better defender than whoever you want to compare him to.”

New York Mets shortstop Francisco Lindor (12) gets the force out of Miami Marlins second baseman Jazz Chisholm Jr. (2) in the 2nd inning at loanDepot park.

Jan. 20, 2021: The Mets hire Zauzmer from the Dodgers.

Zauzmer graduated from Harvard in 2015 with a degree in Applied Math and Computer Science. He gained some renown for using algorithms to predict Oscar winners.

Where once the Mets had one analyst focused on data science, Cohen and Alderson hire several while boosting the R&D department to 19. Alderson decides to have analysts travel with the team this year so information is presented with a human connection, rather than digitally or in print form.

Feb. 20, 2021: The Mets sign free agent pitcher Taijuan Walker, 28, to a two-year, $20 million contract.

April 5, 2021: Opening Day.

With a runner at first in the second inning, Jacob deGrom throws a 94-mile fastball to Jean Segura, the Phillies second baseman. Segura hits it hard up the middle. deGrom jerks his head quickly to watch what last year would have been a base hit. But Lindor, ranging far to his left, snares it with one hand and flips it to McNeil, who turns the double play. Instead of facing first and third with one out, deGrom walks off the field. Inning over.

deGrom is so good that he may be to 2021 what Bob Gibson was to 1968: a pitcher so good the rules of the game will need to change to give hitters a better chance. Do not overlook the role of the Mets’ improved defense in deGrom’s historic season. The Mets have reduced the batting average on balls in play against deGrom by 61 points, including a reduction of 129 points on groundballs and line drives up the middle, when Lindor’s range and their increased use of shifts are most noticeable.

*Linedrives & groundballs

Mets Defense Behind deGrom20202021







BABIP Middle*



Hits Middle*



“The players have trusted the information,” Rojas says. “Starting out, the pitchers don’t like it when a weak grounder gets through the open side of infield for a hit, especially when the pitcher is a Cy Young Award winner. And the pitchers do have a say-so. If they don’t like something about the shift, we listen. But they see it work. They see a ball that goes between their legs and instead of a hit up the middle we turn two behind them.”

April 6, 2021: Stroman, who opted out of last season, makes his first start since 2019.

The Mets turn 12 groundballs into outs behind Stroman, the most behind him since June 18, 2019.

This is Stroman’s sixth season with 10 or more starts. The .272 BABIP against him this year is the lowest of those six seasons.

May 18, 2021: Ronald Acuna bats against Robert Gsellman with a runner at second and two outs.

Gsellman throws a sinker. Acuna hits a groundball up the middle, just to the left of second base.

On July 24 last year Acuna hit a grounder off deGrom to the exact same area, only softer. The Mets did not shift against Acuna then. Rosario, playing shortstop, gave chase but never got close enough to even make a diving attempt. Base hit.

This year the Mets put three infielders on the left side against Acuna. This time the ball is hit directly to Jose Peraza, the second baseman. Last year the same grounder would have been an RBI single. This year it was a groundball out to end the inning.

Why shift on Acuna? Over the past two seasons, Acuna has come to the plate 403 times. He has hit one groundball to the traditional area of the second baseman—where the Mets stationed their second baseman against him last year. Why defend an area with a 1-in-403 chance of getting a grounder when in the same span Acuna hit 25 grounders up the middle?

May 29, 2021: Austin Riley bats against Walker with one out and a runner on first.

Walker throws a split change. Riley hits it back to the box at 95 mph. Walker reaches for it with his glove but is not quick enough to grab it. He turns anxiously as it skitters up the middle, presumably into centerfield. But Peraza, who was shifted to the left side of second base, glides a few steps to his left and easily fields it and turns it into a double play. It is the exact scenario Rojas described before the game: pitchers are watching what were hits through the box turned into double plays.

Walker has been pitching nine years with four teams. The .220 BABIP against him is the lowest of his career.

May 31, 2021: The Mets begin a nine-game trip to Arizona, San Diego and Baltimore, which will take them through the one-third portion of the season.

Pitcher Seth Lugo and first baseman Pete Alonso should return this week. McNeil and Michael Conforto may be back by the end of June. Pitcher Carlos Carrasco will contribute sometime mid-summer. New York will get healthier.

In the meantime, despite the injuries, the Mets have thrived because of pitching and defense. It’s been teamwork of the highest order. Only the Giants and Cubs have a higher groundball rate than the Mets’ pitching staff (46%). The Mets entered play Sunday night with a home ERA of 1.81 through 20 games. That would shatter the live ball record in a full season of 2.07 by the 1966 White Sox, in an era so long ago that Chicago used 13 pitchers the entire season.

It is no longer a small sample. The Mets have made real changes in personnel, philosophy, and application of information. They proved the past four years on the negative side that pitching is never separate from defense. Now they are proving it on the positive side.

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