Yankees Kick Off Offseason, Acquire James Paxton

Yankees Get
LHP James Paxton (Age 30): 11-6, 3.76 ERA, 1.10 WHIP, 208/42 K/BB, 160.1 IP
Mariners Get
LHP Justus Sheffield (Age 22): 0-0, 10.13 ERA, 2.63 WHIP, 0/3 K/BB, 2.2 IP
RHP Erik Swanson (Age 25): 8-2, 2.66 ERA, 1.00 WHIP, 139/29 K/BB, 121.2 IP at Short Season, AA, and AAA
OF Dom Thompson-Williams (Age 23): 22 HR, .299/.363/.546, 20 SB, 156 wRC+ at Class A and High A

Yankees Perspective
The Yankees kicked off the offseason with the first big splash, bringing in an above average major league starter that looks like an ace when he's healthy; unfortunately, James Paxton has never thrown enough innings to qualify for the ERA title (162) as he has struggled to stay on the mound, though he has been healthier the past two seasons. Since 2017, the big Canadian lefty is 23-11 with a 3.40 ERA, a 1.10 WHIP, and a 364/79 strikeout to walk ratio over 296.1 innings; that's pretty darn good. Luis Severino will be back as the ace, but Paxton will fit in well as a #2 starter ahead of Masahiro Tanaka, C.C. Sabathia, and presumably one other yet-to-be-signed free agent addition like J.A. Happ. Losing Sheffield hurts, but Paxton is under team control for both 2019 and 2020 and no pitching prospect is a safe bet. The other two prospects lost were good players in their own rights but didn't really fit into the Yankees' long term plans. For his career, the former Kentucky Wildcat is 41-26 with a 3.42 ERA, a 1.19 WHIP, and a 617/168 strikeout to walk ratio over 102 starts since 2013.

Mariners Perspective
The Mariners never really got over that contention hump, building up a team that was good but not good enough to pass the Astros. Now, they'll start adding to what looks like arguably the weakest farm system in baseball by bringing in three close-to-the-big-leagues talents, and Justus Sheffield immediately becomes arguably the top prospect overall. He's a 6' lefty who put up a strong minor league season with a 2.48 ERA, a 1.14 WHIP, and a 123/50 strikeout to walk ratio over 116 innings between AA Trenton and AAA Scranton-Wilkes Barre. His command is just okay but his stuff is good enough to make him a mid-rotation starter in the near future, and it would not be surprising to see Sheffield break camp in the team's rotation in 2019. Erik Swanson is coming up right behind Sheffield, having dominated at AA Trenton (0.42 ERA, 55/15 K/BB in 42.2 IP) before carrying some of that success over to AAA Scranton-Wilkes Barre (3.86 ERA, 78/14 K/BB in 72.1 IP). He's more of a pitchability prospect with a lower ceiling than Sheffield, but he too could join the 2019 rotation as a back-end guy who can get outs. Having just turned 25 in September, he's an older prospect but that's okay considering he's just about major league ready. Lastly, Dom Thompson-Williams is a little farther off but comes with a high ceiling. Over 100 games between Class A Charleston and High A Tampa, he slashed .299/.363/.546 with 22 home runs, 20 stolen bases, and a 102/33 strikeout to walk ratio, showing power and speed but some rawness in his approach for a 23 year old in the mid-minors. The numbers are great but he's a little old for where he is in the minors and he probably ends up a fourth outfielder if he doesn't shore up his approach in 2019.