When Yuki Matsui burst on the scene as a second-year player for Toko Gakuen at Summer Koshien in 2012, he was a sight to behold. He looked like one of the smallest players on the field, but the diminutive lefty's stature belied the fact that he was a giant with the ball in his hands.

Matsui zipped an array of pitches past opposing hitters, striking out 22 in one game and 19 in another. He was an instant sensation. NPB teams took notice as well, and in 2013 there were five clubs in a lottery for his rights at the draft, with Tohoku Rakuten Golden Eagles president Yozo Tachibana pulling out the proverbial golden ticket.

Matsui had a somewhat rude welcome to life as a pro last season. He began the year in the starting rotation but was sent down with an 0-3 record and 6.05 ERA after four starts, the last straw being an outing against the Seibu Lions on April 23, during which Matsui walked eight in five innings.