Sexson fits in New York because the Yankees needed a right-handed slugger to match up against left-handed pitching -- and Sexson had a .344 average with five home runs in 71 at-bats against lefties this year.
Assuming the deal is completed, he'll be in the lineup Saturday against Oakland.
The Yankees will have to pay Sexson only the prorated minimum of $390,000 from his $14 million salary with the Mariners. Seattle is eating the remainder of the nearly $6 million Sexson is owed for the season.
Sexson was batting .218 with just 30 RBIs in 74 games when the Mariners cut him loose, on July 10. He hit a career-worst .205 with 21 homers and 100 strikeouts in 2007.
A native of Brush Prairie, Wash., the 6-foot-8 Sexson became a frequent target of boobirds in Seattle over the past two years.
Sexson has hit 30 or more homers six times, and also has six seasons of at least 100 RBIs. He started his major league career in 1997 with Cleveland and later played for Milwaukee and Arizona.
Sexson signed a $50 million, four-year contract with the Mariners in December 2004. He topped 30 homers and 100 RBIs in his first two seasons, then dropped off significantly last year.
Buster Olney is a senior writer for ESPN The Magazine. Information from The Associated Press was used in this story.