The Giants have a deal (2 yrs, $7M) with lefty reliever Jake McGee. The 34-year old veteran (11 seasons, 546 games) came up with the Rays and spent time with both the Rockies and the Dodgers. He's a local boy (born in San Jose) but went to HS in Nevada and had his first pro stint at age 17. Lifetime (475-2/3 IP) McGee has a 3.59 ERA, 3.39 FIP, and 3.00 SIERA*. By comparison Tony Watson has a career line of 2.80/3.61/3.47 over 591 innings, and he's a free agent. I assume they don't expect to re-sign Watson and that's why they targeted this guy.
This is a good move as the Giants need lefty arms and competition for spots in the bullpen. Pitchers and catchers report on February 17. I have not heard of a corresponding 40-man roster move to make a spot for McGee.
--M.C.