They don’t have a division lead to show for it, but the Phillies have been one of the top teams in baseball to start the year. Alec Bohm and Trea Turner have carried an above-average offense despite some slow starts from the other usual suspects, and the pitching staff has lived up to its projected excellence, sitting a full win ahead of the field entering play Tuesday. Philadelphia’s substantial investments — from the newly extended Zack Wheeler and the re-signed Aaron Nola to the army of high-leverage bullpen arms — are paying off with interest, with Wheeler leading all NL pitchers in WAR. But sitting just a hair behind him is a teammate who may be having an even finer season: Ranger Suárez.

Suárez first rose to prominence in 2021, a season in which his role transitioned from mop-up reliever to co-closer to the rotation over the course of just a few months. After he recorded a diminutive 1.36 ERA across 106 innings in his breakout year, he earned a permanent spot in the rotation entering 2022. Over his first two seasons as a full-time starter, he’s put up a 92 ERA-, making him a solid mid-rotation arm but a clear step below Wheeler and Nola.

That’s changed this year, as the emergence of Suárez has given the Phillies a third ace to follow up their dominant duo. Case in point: Suárez’s eight-inning, one-run gem on Saturday constituted his worst start in weeks, snapping a 32-inning scoreless streak that included a complete game against the Rockies on April 16. And a quick glance at the numbers shows his superb month was no fluke.

The previous version of Suárez possessed neither plus stuff nor control, instead thriving with a high groundball rate that limited extra-base damage on balls in play. As someone who doesn’t throw hard or spin a hammer breaking ball, improvements to his stuff would need to come from more subtle means than his raw pitch characteristics. If anything, PitchingBot and Stuff+ view his season thus far as a slight step back in that department. But while Suárez hasn’t added a tick to his fastball or learned a new pitch, stronger command and synergy of the pitches he already had have led to big results across the board.

Suárez has a kitchen-sink arsenal, throwing five pitch types with regularity and none more than a third of the time. He most commonly starts hitters off with his sinker, a tumbling seam-shifted wake offering with just 4.5 inches of induced vertical break, which is less than half the league average. It’s doesn’t miss bats, but it has enough run to miss barrels; it’s his best groundball pitch and has a negative average launch angle. It’s also a called-strike machine when Suárez lands it in the zone, which he does about two-thirds of the time.

After getting ahead in the count, Suárez likes to pivot to his curveball and changeup, the latter of which has elevated his performance the most this season. The synergy between any groundballer’s sinker and change is crucial to their success – hitters unsure of what’s coming are more likely to both swing over changeups that dip beneath the zone and watch meaty sinkers go by, both good outcomes for the pitcher. Previously, Suárez struggled to locate his changeup, amassing a -5 run value over his first two years in the rotation. But with a +4 value in just six starts in 2024, it’s clear he’s turned a corner with it.

You might not recognize one of the stats in the above table. JOtZ% doesn’t roll off the tongue like BABIP or xwOBAcon, but it stands for “Just Outside the Zone” percentage – a region I defined as outside the rulebook strike zone but in Statcast’s shadow region. The changeups that are thrown just a few inches off or below the plate are the ones most likely ones to draw chases, making JOtZ% a decent indicator of command. In 2022 and ’23, Suárez often missed too low when throwing changeups – directionally correct in hitting his spots, but so low that no hitters were fooled into thinking they were sinkers. By more consistently finding the few inches directly beneath the strike zone, his JOtZ% shot up, and the results followed.

Most hurlers of his archetype struggle to find an out pitch, but Suárez may have two lethal offerings in the bank. In addition to his better-commanded changeup, his already-good curveball creates an enviable package of secondary stuff. He most commonly uses his curve in 0-2 and 1-2 counts as he fishes for strikeouts, often throwing it in the dirt with success. While his changeup’s success relies on pinpoint accuracy, Suárez’ curveball indiscriminately takes down opponents regardless of location thanks to its excellent two-planed break, with over a full foot of drop and sweep compared to a pitch thrown without spin.

Across the league, Suárez is one of just four starters (along with Tanner Bibee, Jack Flaherty, and Jared Jones) with a 19% swinging strike rate or higher on two separate pitches, which makes it no wonder he’s on pace for a career-high strikeout rate. But Suárez gets his whiffs much differently than his competitors do. One of the best indicators of pure stuff is in-zone whiff rate, the number of hittable pitches that batters come up empty on. High-octane aces like Wheeler, Gerrit Cole, and Spencer Strider top the leaderboards over the past few seasons, as do Bibee, Flaherty, and Jones this year. But while his 27.8% strikeout rate is in the top quartile of pitchers, Suárez’s zone-whiff rate sits in just the 8th percentile.

You could look at Suárez’s struggles to earn whiffs on strikes as a sign that his numbers are unsustainable, but I disagree – because what he lacks in in-zone dominance he more than makes up for by controlling the area outside of it. Because most out-of-zone pitches are taken for balls, the median pitcher loses about two runs of value per 100 they throw. No wonder we consider pitches thrown outside the zone to be mistakes. Except, that’s not the case for Suárez.

Suárez is one of just two starting pitchers in the league to create positive value by throwing outside the strike zone. He uses his non-strikes purposefully, each one carefully placed in an attempt to generate a swing from the batter. Data-driven models are a fan of his approach, with his 108 Location+ ranking sixth in the league. So far, it’s worked wonders for his ability to induce weak contact, shattering his previous bests in wOBA, groundball rate, and barrel rate while leading qualified starters in xERA.

More importantly, Suárez’s out-of-zone pitches don’t just keep the ball on the ground; they also miss bats entirely. He throws his curveball and changeup — his two best pitches at getting swings and misses — in the zone just a third of the time; most offerings that earn so many swinging strikes land in the zone far more often than that. Out-of-zone whiff rate is often thought of as a consequence of good stuff rather than great command – the leaderboard over the past few seasons closely resembles the one for strikeouts – but better command can also boost it. Suárez has improved his out-of-zone whiff rate by five percentage points this season, a year-over-year improvement that ranks in the 91st percentile.

All these whiffs on pitches outside the zone are also allowing Suárez to pitch deeper into games. Over his first two years as a starter, he wasn’t exactly known for volume; he would often get into deep counts, which led to a high walk rate and an average of fewer than 5.5 innings per start. Six starts into the new season, he’s bumped that average to 6.8 innings per start without a significant change in pitch count in part because he’s getting more swings on pitches outside the zone. He’s increased his strike rate from 62% to 66% while slashing his walk rate by more than half. More length from him will be a welcome development on a roster that is, for now, rostering just seven (all single-inning) relievers to accommodate a six-man rotation.

We often think of the pitchers with the best command as the ones who dominate within the strike zone – those with the highest zone rate, those who can hit their spots within it, and those who can limit walks — but Suárez shows us that command is different than control (which is something Jon Becker pointed out in his Top of the Order column Monday). Command is about throwing pitches in the spots that induce weak contact, generate whiffs, and befuddle hitters into making poor swing decisions. Suárez’s improved command has taken him to the next level, and he’s done it with a new approach outside the zone.