Leading up to Opening Day, we’re going to preview all 30 MLB teams and how they could fare defensively in 2021.

A team’s hitting and pitching are easy to evaluate when previewing a season but defense is a little harder because of the nature of the numbers available to assess a player’s skill.

But that sort of thing is our specialty and we’re happy to take our best shot at it.

Today’s look is at the NL West.


Greatest Strengths: Shortstop

Biggest Weaknesses: That they’re not the team of a few years ago.

The Diamondbacks have a great defensive shortstop, Nick Ahmed, who has the most Runs Saved at the position the last three seasons, so they don’t have to worry any there. They have two defenders who were very good two seasons ago in first baseman Christian Walker and left fielder David Peralta, who won a Fielding Bible Award. Both Walker and Peralta were around MLB average in the shortened 2020 season.

Beyond that, most of their players are average. There isn’t a position that would be a major concern, unless Asdrubal Cabrera’s playing every day becomes a necessity (he’s a below-average defender). But there isn’t one that would be a strength either. Their next-best defensive player is probably Ketel Marte, whether he’s at second base or in center field.

Arizona finished first in the majors in Runs Saved in 2018 and third in 2019, but this team is something closer to middling.


Greatest Strengths: Right Field, Versatility

Biggest Weaknesses: None

The Dodgers finished tied for fourth in Defensive Runs Saved last season, but they lost one of the biggest reasons for that in second baseman Kiké Hernández, who left in free agency for the Red Sox. However, Gavin Lux has racked up 9 Runs Saved in 40 games there and should be a capable replacement if he wins the job.

The team is highly secure in right field with Mookie Betts, who has won a Fielding Bible Award in four of the last five seasons. His four are the most of any right fielder in the 16-year history of the award. It should also be more than fine in center field, where Cody Bellinger has totaled 15 career Runs Saved in just over 1,000 innings.

So long as the Dodgers have Austin Barnes on their roster, they know that they can upgrade from Will Smith’s average glove to Barnes’ excellent one at the end of any game they’re trying to close.

Finding a Dodgers weakness is hard. Max Muncy, Corey Seager and Justin Turner are, at worst, average defenders. Muncy, Chris Taylor, and Edwin Ríos can play any number of spots, allowing the team to fill whatever hole it has in a given moment.


Greatest Strengths: Catcher, First Base, Right Field

Biggest Weaknesses: Second Base, Left Field

The Giants will welcome Buster Posey back behind the plate with open arms. That’s not a knock on Joey Bart so much as it is a tribute to Posey’s excellence. Posey has averaged 13 Runs Saved at catcher over the last 5 seasons. He’s still a complete catcher – an excellent pitch frame, pitch blocker and basestealing deterrent.

Brandon Belt totaled 0 Runs Saved in 2020 but averaged 9 from 2017 to 2019 by covering a lot of ground and defending bunts well. We’d normally say you can count on him but offseason heel surgery has us wondering if he’ll be able to make plays as well as he previously did.

Beyond that, Mike Yastrzemski is trying to establish himself as a mainstay. He’s saved 7 runs in just over 600 career innings in right field, which is a good start.

The Giants don’t match up defensively with the other teams in the division though. Their middle infield rates below average, particularly at second base where the Giants options are Tommy La Stella, Donovan Solano, and Wilmer Flores. It’s possible that Evan Longoria could be quite good at third base, but he’s not even guaranteed being a regular starter.

Left field could also be problematic. Alex Dickerson is slated for prominent playing time there. He cost the Giants 8 runs in 270 innings with his glove last season.


Greatest strengths: Third Base

Biggest weaknesses: The uncertainty of second base

The Padres are projected to hit and pitch at high levels. The defense is pegged to be a little above average, with upside if Fernando Tatis Jr. builds on the improvements he made between his rookie and sophomore seasons.

Tatis had considerable trouble on his throws in 2019. He rushed a good number of them and that led to the worst Throwing Runs Saved split for any infielder in the majors (-13 Runs Saved). But in 2020, he upgraded to MLB average (0 Runs Saved). Any further such upgrade could produce a nice bump upwards in his overall defense.

To Tatis’ right is a defensive standout in Manny Machado, who was bettered in Defensive Runs Saved at third base last season by only Nolan Arenado. To his left are some unknowns, depending on how second base is split between Jake Cronenworth, Ha-Seong Kim, and Jurickson Profar.

In the outfield, keep an eye on Trent Grisham, who handled about 500 innings well in centerfield, ranking fourth last season with 7 Runs Saved. His potential makes for another area of upside for this team’s defense.


Greatest Strengths: Shortstop

Biggest Weaknesses: Catcher

With Nolan Arenado and Daniel Murphy gone, shortstop Trevor Story is the full-fledged captain of the infield. Some of the recent changes to our Defensive Runs Saved calculation gave Story’s 2019 season a boost to 21 Runs Saved, which ranked third among shortstops. His 6 last season tied for third most.

Josh Fuentes will be hard-pressed to replace Arenado’s excellence at third base. We track Defensive Runs Saved for our team clients at the minor league level and can tell you that Fuentes’ numbers at the hot corner were excellent. He also looked good in a short stint at first base last season.

Ryan McMahon is slated to play second base, where he’s saved 4 runs in about a season’s worth of games. A small sample size success will get tested if he ever ends up as their regular third baseman. McMahon hasn’t even played 300 innings at the position yet, but he’s already got 10 career Runs Saved. .

With Tony Wolters gone, Elias Díaz will step into the lead catcher role and that could be a cause for concern. In 2019, Díaz cost the Pirates 21 runs with his defense, with a significant chunk of that due to poor pitch framing numbers. Díaz got limited time last season, finishing with 0 Runs Saved in 126 innings in his Rockies debut.

The Coors Field outfield is always challenging to play. Charlie Blackmon (0 Runs Saved) held his own in right field last season. If his teammates can match that, perhaps the Rockies will be able to steal a few victories in what could be a very difficult season.