Yu Darvish was already the master of variety, famously twirling up to 11 different offerings ranging anywhere from the low 60s to the high 90s on the radar gun. But as he puts together his greatest Cy Young Award case to date, with another showcase matchup against Reds ace Trevor Bauer looming Wednesday night, the Cubs’ $126 million ace finally has a money fastball. It took some tinkering by a man long known as cerebral (sometimes to a fault), but now Darvish -- on top of the two cutters, three curveballs, slider, splitter, changeup and “supreme” that he sprays at hitters -- can just rear back and blow hitters away.

Here’s what we mean: entering Tuesday, hitters had taken 47 hacks at Darvish’s four-seam fastball and missed 21 times. That 44.7% whiff rate placed Darvish fifth among the more than 350 pitchers who had elicited at least 25 swings on four-seamers, and No. 1 when that leaderboard is whittled down to qualified starters. Darvish has turned to his heater 40 times in two-strike counts and racked up 13 strikeouts, topping qualified starters in four-seam putaway rate (pct. of two-strike pitches converted to K’s), too, just ahead of Jacob deGrom. Batters have tallied just five singles in 24 at-bats (.208 BA) ending with Darvish’s four-seamer.

Highest 4-seam fastball whiff rate, SP, 2020
Min. 25 swings against (151 SP)
1) Yu Darvish (CHC): 44.7%
2) Dane Dunning (CWS): 43.8%
3) Luis Castillo (CIN): 40.6%
4) Jacob deGrom (NYM): 39.2%
5) Josh Lindblom (MIL): 32.9%
Whiff rate: Misses / Total swings

Highest 4-seam putaway rate, SP, 2020
Min. 25 4-seamers thrown in 2-strike counts (127 SP)
1) Yu Darvish (CHC): 32.5%
2) Jacob deGrom (NYM): 31.9%
3) Kenta Maeda (MIN): 31.8%
4) Trevor Rogers (MIA): 31.7%
5) Keegan Akin (BAL): 29.0%
Putaway rate: % of 2-strike pitches resulting in strikeouts

*Both leaderboards entering Tuesday

Darvish's heater has long shown above-average velocity (he’s averaging a career-best 95.9 mph in 2020), and he’s also routinely ranked among MLB’s top starters in average four-seam spin rate -- something MLB.com’s David Adler highlighted prior to Darvish’s Cubs debut in 2018. Those are, seemingly, the two ingredients for a dominant four-seamer, but Darvish’s cheddar had never played up to its peripherals. As MLB.com’s Mike Petriello wrote when profiling Darvish’s laundry list of pitches a year ago:

"Despite throwing it just under 28% of the time, nearly 39% of his 31 home runs allowed have come off the four-seamer, and the .622 slugging on it is 10th-highest among starters. That this one exists serves mostly to set up the breaking pitches that come along with it; as far as pitches go, this is definitely one of the ones that Darvish throws."

“One of the ones that Darvish throws,” is not how hitters would describe that pitch now. As The Athletic’s Sahadev Sharma detailed this spring, Darvish went under the hood last year and logged on to Ivy, the Cubs’ internal scouting database developed by Theo Epstein and Jed Hoyer’s R&D department, to critique his pitch design and the way his arsenal moved.

Darvish needed to address the way left-handed hitters were battering his fastball (.350 BA, .750 SLG in 2019), and he studied how two of the very best right-handed fireballers, Gerrit Cole and Justin Verlander, got their heaters to ride through home plate. The answer: Put all that spin to work. By simply changing the way he held his fingers on the ball (moving his fingers from the 1 o’clock position to 12, and his thumb from 7 o’clock to directly at the bottom of the ball, per Sharma) in Spring Training, Darvish is getting behind his fastball better with much more active spin.

In prior years, Darvish’s top-of-the-line spin had less productive “gyro” rotation (think of a rifle bullet) that either made it rotate in place or cut. Now, those revolutions are helping the ball ride through the zone. To hitters' eyes, it looks like it's “rising.”

Roughly 87% of Darvish’s 96th percentile four-seam spin rate is now contributing to that desired “rise” effect, compared to just 72% last year. And that means Darvish’s four-seamer now carries 2.5 more inches of vertical movement compared to average four-seamers thrown at similar speeds and release points, after the pitch had never carried more than 1.4 inches above average in any prior season dating back to 2016. Those pesky lefties have struck out more times (seven) than they’ve reached base (four singles and a walk) against Darvish’s super-charged cheese.

“I feel like a lot of hitters are behind my fastballs,” Darvish said last month. “It’s coming out good, I have more rise on it than last year. I want to use it when I want to use it, not every time. That works for me too. Because they have to sit on my fastball too. It’s 96-97 and then I throw a lot of breaking balls.”

That sequencing Darvish alluded to helps his new-and-improved heater play up even more. Darvish is less of a conventional “establish the fastball” starter than he’s ever been before; he throws cutters and sliders on over 60% of his pitches, and he's also throwing roughly half as many four-seamers on the first pitch as he was a year ago. As Bauer, a pitcher Darvish leaned on a lot as he turned things around last summer, told ESPN last week, that pitch mix puts hitters in a bind, because they have to defend both his slowest eephus-like curves and his high-90s heat -- all while he lulls them to sleep with well-placed, mid-80s benders.

"They can't sit fastball, and they can't sit slow," said Bauer. "Pins them in the middle."

Darvish doesn’t need to pound the zone with a four-seamer; now he uses it as an ambush pitch -- surprising hitters with a velocity-ride combo that's giving them fits. It’s strange to think of a fastball with world-class velocity and movement as a secondary strikeout pitch, but that’s a luxury unique to an uber-talented pitcher like Darvish -- and he’s taking full advantage.

This is a pitcher who was already the all-time leader in strikeouts per nine innings, and now his "No. 1" is finally firing up to its potential. That's a scary thought for opponents as the Cubs march toward October.