Rookie phenom Corbin Carroll was the primary storyline in Wednesday’s 6-2 Diamondbacks win over the Washington Nationals. It was Carroll, after all, who had four hits, three runs scored and a stolen base. Carroll was not the only member of his team to reach base four times, though. Ketel Marte did, too.

Marte’s contributions on Wednesday were emblematic of his season as a whole. Rarely has he gotten the big hit; he is on pace for under 70 RBI and had a .418 OPS with runners in scoring position entering play on Friday. Nonetheless, he has been one the club’s most reliable table-setters. From April 26 through June 2, Marte assembled a 30-game on-base streak. It was the longest in franchise history by anyone not named Paul Goldschmidt.

Entering the season, one of the biggest questions facing the Diamondbacks was which version of Marte would show up in 2023. Last year, he had his worst season since joining the club, slashing .240/.321/.407 with 12 homers and 52 RBI in 132 games. It was a precipitous drop-off from the three seasons prior, in which Marte hit .318/.374/.543 in nearly 1,200 plate appearances.

In addition to his decline with the bat, Marte also struggled defensively at second base last year, ranking near the bottom of the league with minus-6 defensive runs saved.

The fact that the D-backs signed Marte to a five-year, $76 million extension prior to the 2022 season made his sudden decline all the more problematic. For better or worse, the D-backs have him under contract through 2027.

So far in 2023, Marte has done a lot to dispel the concerns that arose last year. Entering play on Sunday, he is hitting .277/.345/.472. Those numbers do not line up with the player that Marte once was, but they are good enough to make him one of the better second basemen in the National League once again.

So, how is he doing it? Let’s dive in.

Better swing decisions, especially against lefties

Marte has always been fairly good at laying off pitches against right-handed pitching (as a left-handed hitter), but doing so against lefties has been more of a challenge.

In 2022, Marte had a 35.5 percent chase rate against south paws, which was well above the league-wide chase rate of 29.1 percent. This year, Marte’s chase rate against lefties is down to 29.9 percent.

To be fair, Marte has had some pretty impressive seasons in the past in spite of high chase rates versus lefties. His highest chase rate ever against lefties over a full season was 38.8 percent. That happened in 2019 — his best year ever as a hitter.

In a sense, Marte can get away with it. He has an uncanny ability to do damage on pitches outside the zone. Last year against lefties, Marte hit .324 with a .500 slugging percentage when putting out-of-zone pitches in play. Even in his down 2022 season, those numbers were .290 and .484, respectively.

Marte is excellent at manipulating his powerful right-handed swing to get to nearly any pitch.

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Marte’s ability to mash pitches as a right-handed hitter is not new. He has a career slash line of .303/.357/.520 against south paws.

According to a report from the Arizona Republic’s Nick Piecoro, Marte actually went into the offseason looking to ditch his left-handed swing altogether. It didn’t work out, but it’s not hard to understand why he wanted to try it.

All of this is to say: Marte’s swing against lefties is fantastic, even and especially on pitches outside the zone. At the same time, for as good as Marte is at handling pitches outside the zone, he is — as one would expect — still better at hitting pitches inside the zone.

Marte’s swing decision changes not only bode well this year, but for future years. As hitters age — Marte will be 30 in October — one of the first things to go, according to a 2012 FanGraphs story, is the ability to make contact on pitches outside of the zone. It makes sense, in theory: As bat speed decreases, hitters have to cheat more to get to in-zone fastballs, making them more susceptible to breaking pitches out of the zone.

Although Marte is still doing his damage on pitches outside the zone, his whiff rate on such pitches has actually skyrocketed this year — from 30.1 percent in 2022 to 45.5 percent in 2023.

At this point, it is too early to say whether that is early-season noise or a sign of aging. Either way, Marte will have to learn eventually to be less reliant on out-of-zone contact. The fact that he is making the appropriate adjustments now can only be a positive development.

More damage in the strike zone

We have talked a lot about pitches outside the zone. Now, let’s talk about what Marte is doing at pitches in the zone.

Last year, Marte had the highest in-zone whiff rate of his career at 16.3 percent. In other words, when swinging at pitching in the strike zone, he missed 16.3 percent of the time.

This year, that number has plummeted to 11.5 percent, much more in line with his career norms.

It is unclear exactly what caused Marte to miss as many hittable pitches as he did in 2022, but it was a major contributor to his career-high 18.1 percent strikeout rate.

It also, as one would expect, had a significant impact on Marte’s overall numbers on pitches in the zone. Last year, Marte hit .259 with a .448 slugging percentage on pitches in the zone. This year, those numbers have jumped to .305 and .526, respectively.

Another significant contributor to Marte’s success this year is an increased barrel rate, from 4.3 percent last year to 6.1 percent this year. League average is 4.7 percent.

Put simply, a barrel is a batted ball with optimal launch angle and exit velocity. Barrels often go for extra-base hits, and barrel rate has proven to be more predictive of future power output than other traditional power metrics, such as slugging percentage. For as great as Marte is at getting to pitches outside the zone, all of his barrels in 2023 have happened on pitches in the zone.

Marte’s 6.1 percent barrel rate this year still falls below his 2019 and 2021 marks of 7.2 and 6.7 percent, respectively, but it does suggest that his diminished slugging numbers last year were more caused by poor swing decisions than an actual loss of power in his swing.

Ultimately, it might be unrealistic to hope for another .900-plus OPS season from Marte. But, at the very least, the D-backs’ second baseman has reestablished himself as a force in the lineup, boasting an .817 OPS ranks fourth in baseball among qualified second basemen.

Given the rise of Corbin Carroll, the resurgence of Lourdes Gurriel Jr. and the steady presence of Christian Walker, Marte has been all the D-backs needed him to be.

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Top photo: Scott Taetsch/USA TODAY Sports