Marcus Stroman's 2014 Transformation from Unreliable Rookie to Pennant Race Ace

Mike RosenbaumMLB Prospects Lead WriterAugust 6, 2014

Getty Images

The Toronto Blue Jays (60-54) have dropped four consecutive games, but the team still holds a half-game lead for the second wild-card spot.

A big reason the Blue Jays have remained in the playoff picture is rookie Marcus Stroman, who has been a revelation since joining the starting rotation in late May. And if the team plans on reaching the postseason, it'll need him more than ever over the final two months of the regular season.

However, success in the major leagues hasn’t come easily for the 23-year-old right-hander.

Stroman was used strictly as a reliever during his first stint with the Blue Jays in early May. Coming out of the bullpen, the right-hander tried to overpower and dominate opposing hitters, working in short bursts rather than pitch as he would as a starter—which his why he posted a 12.79 ERA and .419 opponents’ batting average over 6.1 innings.

Since moving into the rotation, however, Stroman has pitched to a solid 2.66 ERA and 64-17 strikeout-to-walk ratio in 71 innings spanning 12 starts. In July, he went 3-0 with a 1.71 ERA and 31-8 strikeout-to-walk ratio in 31.2 innings.

So what has made Stroman so successful as a starter?

To begin, he has thrown fewer four-seam fastballs in each of the past four months and mixed in more two-seamers, which Brooks Baseball identifies as a “sinker.”

The increase in two-seamer usage has in turn improved his ground-ball rate (per Brooks Baseball):

Courtesy of

Meanwhile, it’s a testament to the quality and depth of Stroman’s arsenal that he’s pitched so well as a starter without missing many bats within the strike zone. When he has induced whiffs this season, it’s usually been below the zone—where he likes to bury his slider against both right- and left-handed batters—and above the zone, where he likes to challenge hitters with elevated fastballs.

Courtesy of

Surprisingly, Stroman has the most room to improve against right-handed batters.

Against righties, his two-seam fastball/changeup combination—specifically his two-seam fastball, as previously noted—has been most effective, while his slider and curveball have emerged as consistent weapons against left-handed batters.

Marcus Stroman: Batting Average vs. Pitches (Starting Only)
Four-Seam FBSinkerChangeupSliderCurveballCutter
Brooks Baseball

Though he’s still been highly effective and plenty nasty, Stroman’s struggles to establish a feel for sequencing have been apparent, and his pitch execution obviously still needs work. However, both of those are finer aspects of his overall game and should improve naturally with experience.

Lastly, I’ve always loved how Stroman, who stands 5’9” tall, pitches with the confidence of a 6’4” monster; he doesn’t stand down against any hitter. He’s been a big-game pitcher since his days at Duke, and his tremendous minor league numbers only speak to his overall potential.

That being said, I’d be remiss not to mention that Stroman was shelled in his start on Sunday against the Astros, as the right-hander allowed five runs on seven hits and needed 67 pitches to complete three innings. But I wouldn’t worry about the shaky outing; Stroman has and will continue to hit rough patches this season, which is expected from any rookie pitcher facing the most advanced hitters of his life.

Therefore, I expect that Stroman’s stuff and competitiveness will allow him to continue improving and further the Blue Jays’ success over the final two months of the season. He can’t carry Toronto into the postseason by himself, but he should at least give his team a chance.