Update (6:44 PM ET): The deal is worth $17 million total, per Bob Nightengale of USA TODAY Sports.
Nicasio, 31, spent last season with the Pirates, Phillies, and Cardinals, putting up an aggregate 2.61 ERA with a 72/20 K/BB ratio in 72 1/3 innings. He appeared in 76 games, leading the National League.
Nicasio will help bolster the Mariners’ bullpen behind closer Edwin Diaz. It’s not known exactly what role he’ll have but it seems reasonable to assume he’ll handle mostly the seventh inning while Nick Vincent will set up for Diaz. Nicasio does have plenty of starting experience so he could also spot start in a pinch.