When Carl Edwards Jr. was drafted by the Texas Rangers out of Mid-Carolina High School with the 1,464th overall pick in the 48th round of the 2011 draft, it was almost entirely ignored. After all, players taken that late were largely vanity picks, high schoolers with firm college commitments, or college players with little to no chance of ever reaching the big leagues. You probably didn’t hear about it, either, when he signed for just $50,000 after that 48th round selection.

Edwards Jr., however, was the rare late-round draft pick to sign and go on to make a name for himself as a prospect. In 317⅔ minor league innings, he compiled a 2.21 ERA and 11.4 strikeouts per nine innings, peaking as Baseball America’s 28th best prospect prior to the 2014 season (now as a member of the Chicago Cubs’ organization after a trade during the 2013 season).

Fast-forward two years to the 2016 season, and Edwards is now a key member of a Cubs team that owns a Major League-best 87-47 record. In 26⅔ innings this season, Edwards owns a 3.04 ERA (73 ERA-), 2.06 FIP (50 FIP-), 2.45 xFIP (60 xFIP-), and 2.46 SIERA with a whopping 12.15 strikeouts per nine innings. Obviously we’re still in small sample size territory here, but with an FIP- of 49 and xFIP- of 61, the reliever most similar to him is Kelvin Herrera, widely regarded as one of the league’s top relief pitchers. What has taken him from an afterthought in the 48th round to being among the league’s elite?

Edwards Jr. is a classic two-pitch relief pitcher, with his fastball and curveball accounting for all but four of his pitches thrown this season. As you’d expect for a pitcher with his numbers, both have been well above-average pitches for him. However, it’s the fastball in particular that has really made him dominant.

Edwards Jr.‘s fastball has gotten a swing and miss (or a foul tip) 13.29 percent of the time in 2016, a number that has been bested by only the fastballs of Zach Britton, Sean Doolittle, and Aroldis Chapman—all left-handed pitchers. The closest righty to him is Pedro Baez at 13.08 percent. On the rare occasion his fastball has been put in play—it’s only happened 39 times out of the 346 he’s thrown it—the average exit velocity is just 84.3 mph. That ranks second out of 409 pitchers who have had at least 10 fastballs put in play against them this season, trailing only CC Sabathia—another lefty—with an average of 84 mph. This makes Edwards Jr. the top right-handed pitcher in baseball in both swings and misses and exit velocity allowed by his fastball. What makes his the league’s best right-handed fastball?

At first glance, his average fastball velocity of 95.45 mph looks very good, but these days that isn’t even good enough to get Edwards Jr. into the top 60 among pitchers who have thrown at least 400 pitches this season, so it can’t only be his velocity. Another thing Edwards Jr. is great at is maximizing his six foot, three inch frame to extend toward the plate and make his fastball appear to be faster than it really is. His average perceived velocity—the speed at which the ball appears to be traveling to the hitter, based on the pitcher’s extension and release point—is 96.79 mph, which jumps him up all the way from 62nd to 17th on the fastball velocity leaderboard. It’s the third largest difference between actual and perceived velocity of a two- or four-seam fastball in the league (min. 100 fastballs thrown) and moves him firmly into the upper echelon of fastball velocity.

However, even more than the velocity, it’s Edwards Jr.’s unique ability to combine a high spin rate with a propensity for getting ground balls. Last year, we learned that a high fastball spin rate typically creates a lot of swings and misses, but also a low number of ground balls. For Edwards Jr., though, his high spin rate—at an average of 2,654 RPM, his is the second highest in baseball—has still somehow created a lot of ground balls in addition to the swings and misses. To illustrate this, take a look at his balls in play chart compared to Andrew Bailey and Justin Verlander, the pitchers directly above and below him on the spin rate leaderboard:

You can also see this in Edwards Jr.’s 53.7 percent ground ball rate. Bailey and Verlander currently sit at 40 and 33.5 percent, respectively. A lower ground ball rate isn’t necessarily bad, but typically a lot less damage is going to be done against a weakly hit ground ball than against a line drive or fly ball. It’s possible this is just a quirk of a small sample, but Edwards Jr. also had a 56.5 percent ground ball rate as a minor leaguer in 2015, so this might be a real skill of his.

Turning just 25 years old today, Carl Edwards Jr. has a fastball that is not only elite, but perhaps one-of-a-kind in today’s game. It’s how he transformed himself from a forgotten pick at the tail end of the draft to one of the game’s best relievers.