MLB Prospects: This Date in MLB Prospect Debuts (April 5)

Every morning, I will look back at a memorable MLB debut made on this specific date using information provided by Baseball Reference’s MLB Play Index.  

Making his MLB debut on April 5, 2007, all eyes were on Daisuke Matsuzaka of the Boston Red Sox.

Signed to a six-year, $52 million contract prior to the 2007 season, Daisuke's gyroball  became a widespread fascination among baseball fans, as their expectations for the right-hander grew exceedingly lofty.

Facing off against flourishing ace Zack Greinke and the Kansas City Royals, Matsuzaka appeared to be worth every bit of the hype, as he led the Red Sox to a 4-1 victory on the road.

The 26-year-old carved up the Royals’ lineup, allowing one run and scattering six hits over seven sharp innings.  Although that particular team was strikeout-prone from top to bottom, Daisuke’s 10 strikeouts and one walk were nonetheless impressive.

Matsuzaka’s first big-league outing—in which he threw 74 of 108 pitches for a strike—was good for a RE24 of 2.9.  The lone run he allowed was a result of a solo shot by David DeJesus to lead off the bottom of the sixth.

He ultimately finished the 2007 season with a 15-12 record and 4.40 ERA while logging 204 2/3 innings.  Although he did post the best K/BB rate of his career (201/80), he also served up a career-high 25 home runs.

Matsuzaka finished fourth in the AL Rookie of the Year voting that season, and followed with the best season of his career (18-3, 2.90 ERA) in 2008.

He hasn’t pitched in the Major Leagues since May 16, 2011, when it was announced that he required season-ending Tommy John surgery.  However, it’s been rumored that Matsuzaka may be ready as early as June, though I’ll believe it when it happens.