Rookie Roberto Osuna Has Been a Dominant Force for Blue Jays

This story originally appeared on VICE Sports Canada.

It's absurd to think now, but it seemed at first like Roberto Osuna was only getting a shot with the Blue Jays because he was Miguel Castro's caddy.

The two 20-year-olds were the stars of spring training for the club, but much of the focus was on Castro, the tall and lanky Dominican with huge hands that he used to throw a biting slider, a changeup as hard as Mark Buehrle's best fastball, and his own heater that would occasionally touch triple digits on the radar gun. Always behind him, though, was Osuna, helping Castro with his English, and joining him in asking to ride the buses to away games they weren't scheduled to pitch in, just to soak up the major league atmosphere, to better understand what it takes to be a big leaguer, and partly, no doubt, to make an impression.

By the end of March the pair were the youngest players left playing games for the Jays by a long shot, with the rest of the prospects their age having been assigned to the club's minor league camp. Though they had been starting pitchers throughout their minor league careers, the Jays had different plans for their 2015 seasons, parting ways with struggling veteran relievers on minor league deals, and sending down former All-Star setup man Steve Delabar to make room for the pair in a patched-together bullpen that looked awfully vulnerable.

With Delabar not having pitched well enough to earn a spot, Brett Cecil struggling to regain velocity after a bout of shoulder tightness to begin the spring, and Aaron Sanchez—who had been a revelation in the bullpen at the end of 2014—assured a place in the rotation after the club was blindsided by Marcus Stroman's season-ending knee injury, the Jays needed to go north with the arms who could best help them close out games, regardless of experience. So they turned to Castro, with Osuna seemingly tagging along.

When Cecil struggled out of the gate, they again turned to Castro, while Osuna accrued valuable service time in the majors as a middle reliever, pitching in losses, and sometimes taking the ball in the fifth or sixth inning early on. It was around that point that their courses began to diverge.

Castro only pitched 12 1/3 innings before he was sent down, struggling badly after being thrust into high-leverage situations—he was the last pitcher the Jays called on in nine of his thirteen appearances. He generated soft contact on just 7.7 percent of balls in play—the third-lowest mark of 460 pitchers with a minimum of 10 innings pitched this season—and his percentage of hard contact against, 41 percent, is among the ten highest in that group.

A 100 mph fastball, if straight, or not located well, doesn't fool big league hitters the way it does in A-ball, which is where both he and Osuna finished the 2014 season, before their remarkable rises this spring. It's where Castro is again pitching now on a rehab assignment after some time off due to a hand injury.

Castro may again be a factor for the Jays this season, general manager Alex Anthopoulos told reporters Wednesday. If he does return, it will be to quite a different bullpen.

That's because his former caddy has quickly established himself as the top reliever on the team, and maybe one of the better ones in baseball, too. Dave Cameron of FanGraphs made Osuna one of his picks for the American League All-Star team, and while it's unlikely that he'll earn that distinction on the actual All-Star team, there's no question that the beginning of his career has so far been sublime. It's only gotten better as the stakes have grown higher, too.

Osuna's numbers are just outside of the elite range among relievers. He's among the top 30 relievers in baseball by strikeout rate, the difference between his strikeout and walk rates (K-BB percentage), ERA, swinging strike rate, and is in the top five by FanGraphs' version of wins above replacement. In June, as he's ascended up the pecking order and into the closer's spot—a job that's all his but in name—his strikeout rate and K-BB percentage both have jumped into the top ten.

Maybe just as important for the Blue Jays, and their long-suffering fans who have seen too many games pissed away by the bullpen already, he's doing it with poise. With confidence. With balls. "He's got guts," Alex Anthopoulos said on the radio in Toronto this week. "We call it something else, but I'm going to stick with guts on this show." It's something that he needed to have before the Jays ever signed him, pitching against men in the Mexican League when he was just 16 years old.

That doesn't mean much if he doesn't have the stats and stuff to back it up, but Osuna does. He doesn't quite light up the radar gun like Castro—his fastball has averaged a "mere" 95-plus mph this season—but it moves enough and he's deceptive enough with it. He's also able to keep hitters off-balance with strong secondary pitches that they have a hell of a time catching up with his heater, and a hell of a time making good contact when they do.

In fact, speaking of that secondary stuff, Osuna has a starter's repertoire, a starter's body, and in all likelihood is going to continue being a starter as his career continues. But it should now be of no small comfort to the Jays that if he ever struggles in that role in the future, they could always ask him to come in and save their bullpen.

It wouldn't be the first time.