Perhaps the biggest winner of the Josh Hader trade to the San Diego Padres is the dominating set up man for the Milwaukee Brewers, Devin Williams (rostered in only 38% of ESPN leagues). He is already among the leaders in fWAR for relief pitchers and on pace to break the major league record of 41 holds, set by several pitchers. Williams has 25 holds and last permitted a run nearly three months ago. He may strike out 100 hitters this season. Give him saves and wow, he's on par with Edwin Diaz and other top fantasy closers, including Hader.
It seems unlikely the Brewers will continue to have struggling lefty Taylor Rogers close for them. He has gave up runs in three consecutive outings and recently lost the Padres' closing role to Luis Garcia. Rogers has been way too hittable with his fastball over the past month and fits better in a setup role anyway. Wait to see how the Brewers react for sure, but Williams should close, making him worth universally rostering, while we can now likely part with Rogers.
Hader takes over closing duties for the Padres and while there was a brief run of home run trouble in mid-July, all is well today. For those in the fantasy world that rushed to add Garcia, sorry. Hader's acquisition is a major upgrade for the Padres, but it shouldn't alter his individual fantasy value.
The Brewers also receive speedy outfielder Esteury Ruiz and right-hander Dinelson Lamet in the trade. While Lamet was once a very promising starting pitcher with monster strikeout potential, he couldn't stay healthy and now is a struggling middle reliever. Ruiz, however, is someone to watch, should the Brewers give him opportunity to supplant Tyrone Taylor in center field. Ruiz hit .333 with a 1.028 OPS and 60 stolen bases in 69 attempts over 77 games for two minor league teams this season. If he plays in Milwaukee (he has already been sent to Triple-A Nashville), he may pile on the stolen bases and offer significant fantasy value in roto formats.