TORONTO -- Marcus Stroman has asserted himself as the Blue Jays' best starter since he made his rotation debut back in late May, wowing teammates, opposing hitters, pitchers and managers with a six-pitch repertoire that has propelled him to prominence in his rookie season.
Following a forgettable five-outing stint in the bullpen, the 23-year-old was briefly optioned to Triple-A Buffalo, but Stroman returned to the Majors with a bang three weeks later. It's hard to believe that just a few months ago, dissenters were questioning the viability of a big league starter with a 5-foot-9 frame.
Apart from the hype that comes with being the No. 1 prospect in a big league organization, it wasn't until Stroman's first career start on May 31 that the baseball world knew he had arrived. After allowing just one run in six frames in a 12-2 win over the Royals, he was asked about his mix of pitches -- including his slider, which it seemed like he used to fan several hitters.
Stroman had to correct reporters: It wasn't actually a slider.
"That's my curveball," he said.
It's that deception -- and the unpredictability of what he will throw next -- that has helped Stroman become a force.
Stroman's decision to expand his mix to six pitches is the product of an insatiable curiosity. He always has a baseball in his hands, and whether he's sitting in the clubhouse, observing from the dugout or just watching television, he's constantly playing around with new grips. Stroman had been working on his changeup since Spring Training, but instead of squarely focusing on the offspeed pitch, he added a two-seam fastball for good measure.
It's art meets science for the native of Medford, N.Y., who spends as much time experimenting as he does visualizing how he might put his own stamp on a traditional sinker or changeup. Stroman has picked the minds of guys like Pedro Martinez, Mark Buehrle and Felix Hernandez, and he has applied those insights to make his own repertoire better.
"Pitching is unique to everyone," said Stroman, who is 7-5 with a 3.28 ERA in 16 starts. "Their hold is different; their delivery is different. I'm not going to go out there and do what someone else does. But I'll see how he does it, tweak it and make it my own.
"It's an art form in that way. It's fun. I'll play around, find grips and go out and throw them, and see how they move."
One thing that's evident when Stroman digs into the topic of pitching is the sheer excitement with which he discusses the topic. Recalling what it was like to introduce a two-seam fastball into his arsenal in mid-July, he lights like up a Christmas tree.
"I have a sinker now, and it's good," Stroman said, proudly. "It's a good pitch, and I get excited when I throw it. I get excited on the mound. It's a pitch I started throwing like a month ago, and I'm already using it in games and having success with it.
"Pitching excites me. ... When you get in a game, and [you've been] working on [pitches] and talking to people about them, and then you execute, it's kind of a 'wow' moment."
For a peek inside Stroman's head, we asked him to break his stuff down for us pitch by pitch, with Brooks Baseball supplying usage and velocity figures.
Curveball: 15.47 percent usage, average of 83.13 mph
Some refer to Stroman's curveball as a "slurve" because of its 2-to-7 o'clock break. He said he likes to try to bounce the hook in on lefties, though he's comfortable throwing it to both sides of the plate. Stroman's lowered arm slot dictates that he looks for more horizontal movement than a traditional 12-to-6 curve. The speed of his curveballs varies between 80-85 mph.
"It's been a huge pitch for me, but I've gotten away from it a bit lately," Stroman said. "It's more 'slurvey.' It's a pretty safe pitch for me to get off the barrel, and I have pretty good control of it to both sides."
Cutter: 18.37 percent usage, average of 91.49 mph
Sometimes, less is more, as is the case for Stroman's cut fastball, which he throws from about the waist up and tries to turn late, but just a little bit. It's that last-second cut that throws off hitters.
"Usually [I throw it] to get [inside] on lefties," Stroman said. "I feel like it gives lefties trouble, because [it breaks] pretty late. It looks like a heater all the way, and it's a small, all-lateral movement. It can really jam lefties. I'll throw it to righties to get off the barrel, or if the sinker isn't working that day. Or it could be for a double-play ball that I'll go to it occasionally. It's an early-count pitch."
Changeup: 6.77 percent usage, average of 86.05 mph
After taking some pointers from Hernandez during a recent road trip to Seattle, Stroman continues to work on the pitch that he set out to refine in Spring Training. His grip stands somewhere between a circle change and a split-finger fastball. Stroman acknowledges it's a work in progress, but that doesn't prevent him from letting it loose during game action.
"I'm always playing with changeup grips," Stroman said. "It's a pitch I really want to get to be one of my better ones. It's usually effective, because of the speed difference and arm action."
Four-seam fastball: 42.02 percent usage, average of 94.47 mph
Old faithful. For Stroman, there's nothing quite like a well-placed fastball. When it's effective, his heater can be deadly, as he keeps hitters off balance with his other five pitches.
"That's the 'here it is, hit it,'" Stroman said. "That's what you go to when you need strikes. Usually you've probably got the best command of it."
Two-seam fastball: 11.66 percent usage, 93.45-mph average speed
As mentioned before, this relatively new member to the Stroman pitch family was conceived in the clubhouse in an "a-ha" moment not long before his start against the Rangers on July 19, in which he threw seven shutout innings. He used it to considerable success against the Tigers in a brilliant nine-inning no-decision on Aug. 9, during which he induced 16 ground balls. It figured heavily again in Stroman's win over Boston on Wednesday, when the Red Sox hit 17 grounders.
"It has really good action on it," Stroman said. "It was awesome to get off the barrel, front dooring it to lefties, where they're taking it, thinking it's coming in. That's been a huge pitch for me, as well."
Slider: 7.07 percent use, average of 87.90 mph
Stroman uses his slider less than his curveball and cutter, but with the same success. He's just a little more picky with it.
"Sometimes I'll go with the slider over the curveball if I'm facing a predominantly righty lineup, or depending on lefty-righty splits," Stroman said.
Jamie Ross is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.