The Mariners and Yankees completed a trade Monday that sends ace left-hander James Paxton to New York for three prospects, including top-rated lefty Justus Sheffield.
The other two prospects going to Seattle are outfielder Dom Thompson-Williams and right-handed pitcher Erik Swanson.
Paxton, 30, has spent his entire career with Seattle. He went 11-6 in 28 starts last season with a 3.76 ERA.
A first-round pick of the Indians in 2014, Sheffield is the Yankees’ No. 1 prospect and made his major league debut in September with three relief appearances.
The 22-year-old went 7-6 with a 2.48 ERA in 25 games (20 starts) with Double-A Trenton and Triple-A Scranton/Wilkes-Barre this year.
Swanson, the Yankees’ No. 22 prospect, was promoted to Triple-A last season, where he went 3-2 with a 3.98 ERA in 13 starts.
The Yankees picked Thompson-Williams in the fifth round in 2016. The 23-year-old hit .299 with 22 home runs in A-ball with Tampa and Charleston this year.