Boston Red Sox reliever Joe Kelly’s fastball tied his own season-high velocity, which also stands as the fastest pitch of the 2017 season.

Two outs, bottom of the seventh inning with the Boston Red Sox clinging to a two-run lead. There’s a man in scoring position with New York Yankees slugger Aaron Judge at the plate facing reliever Joe Kelly.

Power vs power.

Kelly showed the type of power his arm wields when he uncorked a fastball on a 2-2 count. Judge fouled it off to stay alive, making the pitch seem almost meaningless at first. Until you looked up at the scoreboard to see the velocity on that fastball.

The Yankee Stadium gun registered the pitch at 103 mph, while the Red Sox radar on NESN clocked it at a whopping 104 mph. Social media started buzzing about what may have been the fastest pitch of the year, with many surmising the actual velocity was somewhere in between.

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MLB Statcast would later officially record the pitch at 102.2 mph, which is tied for the fastest pitch thrown in 2017.

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Who did Kelly tie for the season high? Himself, of course. Kelly previously reached 102.2 mph on April 28 with a fastball to Chicago Cubs star Anthony Rizzo.

As impressive as the velocity on Kelly’s fastball was, the same can be said for the bat speed of Judge to be able to catch up with the pitch to foul it off. If Kelly was shocked that the pitch didn’t put Judge away, he wasn’t fazed by it. The hard throwing right-hander came back with a 92 mph slider to strike him out and escape the inning.

Stadium radar guns can be inconsistent, with teams often accused of juicing the velocity for their own players. The Statcast results are what will go down in the record books, which are impressive enough on their own.

Had Kelly been credited with the 104 mph that NESN showed, his fastball would have gone down as one of the five fastest in history. Nolan Ryan holds the major league record at 108.1 mph, followed by Bob Feller (107.6), Aroldis Chapman (105.1) and Joel Zumaya (104.8). Chapman has the fastest velocity since the modern Pitch F/X data hast been tracked, while the fastballs of Ryan and Feller were recorded using older methods that may be less reliable.

Kelly is averaging a career-high 99.1 mph with his two-seam fastball this season, which is his most commonly used weapon, per FanGraphs. The uptick in velocity clearly stems to his new full-time role in the bullpen, where he’s able to unleash the full force of his fastball pitching in shorter stints.

Unlike other relievers who throw this kind of gas, such as Chapman or Red Sox closer Craig Kimbrel, Kelly hasn’t been piling up the strikeouts. His current 6.39 K/9 rate is his lowest since 2014 and a steep drop from last year’s 10.80 K/9. We can’t complain too much about a lack of strikeouts when Kelly owns a stellar 1.42 ERA, although a 2.94 FIP suggests his success may be a bit of smoke and mirrors.

Perhaps the greatest benefit of Kelly’s increased velocity in the bullpen is that even when hitters are able to catch up with his fastball, they don’t have enough time to square up the pitch on their bats. This can result in weak contact, which explains his career-low .239 BABIP. This is often passed off as a fluke, although it may not be for a pitcher who routinely throws triple-digit heat.

Kelly couldn’t quite set a new season-high as the radar guns in the stadium suggested, yet he still had more than enough gas for the Yankees to handle. He’s not your typical fire-breathing strikeout machine but it’s becoming clear he doesn’t have to be. Kelly still possesses a power arm that has made him a trusted reliever to handle a tight spot late in games. His emergence has helped cover for the loss of two of Boston’s top relievers and transform the bullpen into one of the league’s best.