The righty has some of the nastiest stuff in baseball.

I can’t begin to imagine how much relief pitchers hate the current extra-inning rules. Welcome to the game. Through no fault of your own, there’s a runner on second base with nobody out. If you do your job well and get a ground ball and a flyout, you’ve likely lost the lead. Good luck!

The Situation

Pretty much exactly what I said above. It’s the top of the tenth inning with the score tied at three against the Tampa Bay Rays.

Zack Kelly takes the mound for the Red Sox, looking to find a way to keep the runner at second base.

1: Richie Palacios

Palacios has almost exclusively played against right-handers this season, pulling the ball frequently. He also hasn’t hit the ball on the ground a ton but does strike out frequently. In this situation, a strikeout is always valuable, but even more so with a hitter who can hit the ball to the right side at the plate.

Kelly starts the outing with a beautiful changeup low and away for a strike. Most hitters, Palacios included, are looking for something to drive on the first pitch of an at-bat. This isn’t that, so it’s a free strike. 0-1.

This is hardly fair. After a 78 MPH changeup, Kelly starts the pitch on the outside corner, but this time it’s 96 MPH and straight. It dots the corner for the second strike. At 0-2, I’d continue to work away from Palacios and avoid giving him something he can get to the right side with ease.

Kelly tries to elevate with the fastball and misses away. A quick look at the scouting report tells me that Palacios doesn’t handle the high fastball very well, making this a great option. It’s too far off the plate to get a swing, but also not in a dangerous location. No harm, no foul. At 1-2 after back-to-back fastballs, I’d likely go back to the changeup away. Another high fastball isn’t a bad idea either.

He does throw the changeup and totally fools the hitter. The pitch stays up just a hare and allows Palacios to get the bat on it. I’d throw another changeup, but the high fastball remains in play as well.

Strike three. This is meant to be a backdoor cutter, but misses inside and gets the swing and miss. I don’t love backdoor pitches to the glove side in general (more on that here), but it gets the job done here. At the very least, an arm-side cutter would set up the changeup on the following pitch, but in a two-strike count with a hitter who whiffs a lot at the plate, I don’t think you need to be setting up a 2-2 changeup. I’d prefer to see Kelly go right after him. Either way, it’s strike three for the first out of the inning.

2: Jonathan Aranda

With one out, Kelly will be able to live with a sacrifice fly or a groundout. Even a walk isn’t the end of the world if he finds himself in trouble. First pitch sweeper for the whiff. Aranda is a bit earlier, but not too far off of it. I’d go away from the sweeper here and think about a changeup outside.

Backdoor sweeper for strike two. I don’t love it in two-strike counts when the hitter has to fight it off, but it works for a called strike when the hitter can afford to take a pitch. Again, I’d go to the changeup.

I can’t tell if this is a missed spot or gamesmanship from McGuire with a runner on second. He starts the target high before lowering his glove. The pitch ends up down in the zone and Aranda taps it back to Kelly for the second out of the inning. Part of what makes Kelly so difficult to hit is how well he changes velocity. Aranda saw two 83 MPH sweepers, and then a 96 MPH fastball. Kelly also has elite extension, making that 96 feel more like 98.

It’s hard to say how much influence a pitcher has over hitter bat speeds, but Kelly has seen extraordinarily slow swings so far this season. I won’t say definitively because he mixes his velocities so well that it’s hard for hitters to swing with conviction frequently, but that could be the case. It could also be a small sample size. Just some food for thought. Regardless of the reason, Kelly’s fastball generates ground balls at a great rate at an excellent rate, and he gets an important one here.

3: Harold Ramirez

Two outs. Get the out and you’ve given your team a great chance to win the game in the bottom half of the inning. No pressure. Here’s a sweeper that totally fools Ramirez. He’s likely looking for a fastball middle-in and fails to pick up the spin here, resulting in an ugly swing. Now that Ramirez has tipped his hand by swinging for a fastball, I would throw the sweeper for at least the next two pitches, if not more.

This one goes about 58 feet. It never looks like a strike, and Ramirez doesn’t need to give it much thought. Still, I would throw another sweeper because the hitter hasn’t proven he can lay off a good one. Even if he does lay off a good one, I’d probably throw it again.

Ramirez, still looking for a fastball, is frozen by the sweeper and can’t bring himself to pull the trigger. With two strikes, you could get cute and show him the first fastball of the at-bat, but I’d continue with the sweeper because he clearly isn’t seeing it well.

Baseball is fun. It’s a fourth sweeper and Ramirez still can’t connect. Sometimes, it’s really that simple. If Kelly had to face Ramirez a second time, I would advise him to continue throwing the sweeper until Ramirez takes two consecutive off the plate, or puts one in play. Sometimes, just the threat of throwing a 97 MPH heater can be enough to give a hitter pause when sitting on an off-speed pitch.

Zack Kelly has only pitched ten innings for the big league club this season, yet I still find myself with a sense of comfort while he’s on the mound. It’s not often that a relief pitcher has multiple plus pitches that he can throw to either side of the plate. Among relievers with over ten innings pitched (a convenient qualifier), Kelly’s fastball ranks 22nd of 212 in Stuff+, his changeup 11th of 127, and his sweeper 62nd of 211. Stuff+ isn’t the end all be all, but Kelly is seriously nasty. Outside of one poor outing, he’s been fantastic in his appearances this year. As the season progresses, I’d look for Kelly to pitch in higher leverage spots as he climbs the reliever rankings.