As college freshmen across the country begin cramming for final exams, Brandon Barriera was busy acing a test of a different sort on Wednesday night.

Toronto's No. 2 prospect twirled four hitless frames and struck out six in his professional debut for Single-A Dunedin, which held on to defeat Fort Myers, 5-4, at Hammond Stadium.

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Flashing a biting slider and crackling fastball, Barriera looked the part of a first-round Draft pick, slicing through the Mighty Mussels' lineup on just 49 pitches, 30 for strikes. The 19-year-old topped out at 95.8 mph with his fastball, but it was his slider that proved to be his most effective pitch.

The southpaw generated seven whiffs on 22 sliders, including four of his six punchouts. Barriera's only blemish was a leadoff walk in the second inning, but the runner was quickly erased on a stolen-base attempt. Barriera ended his debut by striking out three of his final four batters -- all in succession bridging the third and fourth innings -- and didn't toss more than 14 pitches in any frame.

Barriera gave the Blue Jays exactly what they envisioned when they drafted him last summer. With a bravado that is perhaps only superseded by his prized left arm -- the Brooklyn-born and Florida-raised hurler famously said after he was drafted that the teams who passed on him would "regret this" -- Barriera appears ready for the challenges pro ball will throw at him.

He was certainly well rested, having not pitched competitively since his abbreviated senior year at American Heritage High School in Plantation, Fla. Barriera played it safe and made just eight starts, posting a 5-0 record and a 2.27 ERA to go with 68 strikeouts in 37 innings.

"He's the best pitcher we've ever had come through here," American Heritage head coach Mike Macey told MLB.com last summer. "I'm not even going out on a limb to say that. I think that's pretty obvious. He's the only pitcher that we've ever had you'd consider to be a first-round guy. He's got the most hype around him."

Hype Barriera more than lived up to in his pro debut.