Matsuzaka made his first major league regular season start for the Red Sox on April 5, 2007, in an afternoon game against the Kansas City Royals at Kauffman Stadium. He walked one, recorded 10 strikeouts, and at one point retired 10 consecutive batters. He allowed only a solo home run on 6 hits while throwing 108 pitches (74 for strikes) over 7 innings and recorded the win as the Red Sox triumphed by a score of 4–1. He was, however, beaten 3–0 by Félix Hernández (who pitched a one hitter), Ichiro Suzuki, Kenji Johjima, and their Seattle Mariners in his Fenway Park debut on April 11, 2007 and defeated again, 2–1, by the Toronto Blue Jays in his third major league start despite striking out 10 Toronto hitters in only 6 innings. Matsuzaka still became the only pitcher to strike out 10 or more batters in 2 of his first 3 big-league starts since Fernando Valenzuela did so in 1981.