You can count on one hand the number of successful starting pitchers the Yankees have produced in the Brian Cashman era.
Andy Pettitte is without a doubt the gold standard. The lone starting pitcher from the Core Four won 219 ballgames for the Yanks over 15 seasons, and another 19 in the postseason — an MLB record. Pettitte redefined himself throughout the years; he was a workhorse in his early twenties, eclipsing 200 innings five times between 1995 and 2001. As he grew older he became more crafty, often out-thinking hitters with a mix of cutters, sliders, and curveballs.