Dyson, who started the year with Class A Dunedin, is the latest in a series of moves to address an overworked bullpen. He is expected to serve in a middle relief role as the club attempts to bridge the gap to its late-inning relievers.
The 24-year-old Dyson is known for his mid-to-upper 90s fastball with hard sinking action, and an above-average slider-curveball combination.
"All reports by the development staff is that he's ready to help at the Major League level," Blue Jays manager John Farrell said. "Power stuff, maybe the best overall stuff in our organization."
Dyson made his Major League debut for Toronto in the seventh inning and faced two batters, walking one and striking out one, as the Blue Jays dropped a 9-6 decision in the series finale.
Dyson becomes the first member of the 2010 Blue Jays' Draft class to make the big leagues. He was originally expected to go in the first round, but a right elbow injury impacted his value.
The native of Florida dropped to the fourth round and eventually had Tommy John surgery -- forcing Dyson to miss the entire 2011 season. Dyson returned this year initially as a starter before being transitioned into the bullpen in June.
"I think I responded pretty well," said Dyson, who allowed just two runs in 24 innings out of the bullpen for New Hampshire. "I mean, starting you can kind of, not cruise through a few innings, but you can kind of find it.
"In the 'pen you can't really find it -- you either have it or you don't. And if you don't have it, you're out of there in a few pitches. And if you have it, you're out of there in a few pitches. One is better than the other."
The Blue Jays have yet to make a decision on whether Dyson projects as a starter or a reliever in the future. But he will spend this season in the bullpen, and for now will not be permitted to pitch on back-to-back days.
In addition to the right elbow injury, Dyson also has dealt with an ulnar nerve transposition and bone spurs in his right shoulder. He has already been through a lot during his brief professional career, but the Blue Jays feel he is now ready for the next step.
"Going into his Draft year from South Carolina, he profiled and had the potential as a No. 1 pick but some injuries forced his Draft status to drop a little bit," Farrell said. "He's obviously come back healthy and the stuff has returned."
Dyson filled the spot of right-hander Scott Richmond on the 25-man roster. Richmond was optioned to Triple-A Las Vegas following Wednesday night's game against Kansas City.