Lee, 24, was a first-round pick in 2010 and is currently 7-5 with a 4.89 ERA in 13 starts at Triple-A Oklahoma City. He is 6 feet 4 and 227 pounds. Lee will report, at least for now, to Triple-A Tacoma.
"He’s a young, athletic, and an excellent strike thrower with a good pitch mix," general manager Jerry Dipoto said. "He provides immediate depth, and we feel like the change in scenery and new opportunity could give him a boost."
Lee also provides the Mariners with some flexibility because he has an option remaining for next season. He made his major-league debut last season by pitching one game for the Dodgers.
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The trade comes with the Mariners scrambling to plug holes in their rotation. Felix Hernandez and Wade Miley are currently on the disabled list, and Taijuan Walker left a second straight start Sunday because of tendinitis in his foot.
Taylor, 25, is batting .312 in 63 games at Triple-A Tacoma, but his future in the organization dimmed this season when he was optioned back to the Rainiers after making two errors in his only big-league appearance.
Lee was ranked by Baseball America as one the game’s top 100 prospects prior to the 2011, 2012 and 2014 seasons, but he has yet to match that potential. He is 52-46 with a 3.98 ERA in 139 games over six minor-league seasons.
Taylor was the Mariners’ fifth-round pick in 2012 and reached the majors in 2014. He batted .240 with a .296 on-base percentage in 86 games over parts of three major-league seasons.
Bob Dutton: @TNT_Mariners