As a Yankee the past three seasons, Burnett is 34-35 with a 4.79 ERA. He is 121-111 with a 4.10 ERA in 13 seasons with the Yankees, Blue Jays and Marlins.
The Pirates will send right-handed reliever Diego Moreno and outfielder Exicardo Cayones to New York in return. Moreno, a 25-year-old from Venezuela, has split the past two seasons between the Class A and Double-A minor league teams. Cayones, who is 20, spent 2011 in Class A.
On Sunday, Burnett will take his physical -- while his new teammates are going through the first workout for pitchers and catchers.