The Washington Nationals addressed their bullpen issues in one move without trading any of their top three prospects (Victor Robles, Juan Soto and Carter Kieboom). It's hard for them to do much better than this, even if they did give up a very promising teenaged arm and former high draft pick in Jesus Luzardo. The Oakland Athletics did reasonably well too, both in acquiring a pair of useful prospects and in clearing money for 2018 that would be better spent elsewhere than the bullpen.
Lefty Sean Doolittle has walked just 20 batters unintentionally since the start of 2014, a rate that's less than 4 percent of his total batters faced, and he's death on left-handed batters: He has retired all 24 he's faced this year and has held them to a .184/.213/.299 line in his career. He can get righties out too, and he could slot into any spot in a major-league pen. The story of Doolittle's career is that he's good when healthy, but has had trouble staying healthy, missing most of 2015 and large parts of 2016 and this season.
Ryan Madson has been good to great since missing three seasons (2012-14) after Tommy John surgery and further injuries while he tried to come back, with 2017 his best season yet, already worth 1.6 WAR with just four unintentional walks for a rate just a shade less than 2 percent. With a changeup as his best pitch, Madson has always been effective against hitters on both sides of the plate, with no significant platoon split over the past three years, and since missing all that time he has been durable.
If the Nats wanted to build a bullpen that wouldn’t walk anyone, they have succeeded, and they've more than made up for the loss of Koda Glover to shoulder inflammation, adding two guys who can handle high-leverage work. Even if the Nats had been willing to part with one of their top three prospects, they may not have done any better in the market; maybe they would have acquired someone more famous, but probably nobody more effective.
The A's clear quite a bit of future salary in this deal. Doolittle is guaranteed $5.38 million between his 2018 salary and option buyouts, while Madson is due $7.67 million next year, money that the low-payroll A's probably shouldn't spend on relievers. In exchange, they get back one of their former players in right-hander Blake Treinen, a perfectly capable right-handed specialist for the middle innings, and two prospects, 19-year-old lefty Jesus Luzardo and infielder Sheldon Neuse, both selected in the 2016 draft. Luzardo is the bigger prize, slipping to the 35th overall pick last year after he had Tommy John surgery during his senior spring in high school, but he's back pitching in the Gulf Coast League with fastball heat that's sitting 94-95 mph and touching 97, while also flashing an above-average changeup and average curveball. He has faced 54 batters so far, punching out 15 and walking none. He had No. 2 starter upside prior to the injury and it sounds like his raw stuff is most of the way back already.
Neuse was the Nats' second-round pick last year, and was too old for the Sally League this year at 22, hitting .291/.349/.469 and splitting time between shortstop and third base. I don't think he's a shortstop in the long run, but he could play second or third, or play short well enough to be a utility infielder, with an above-average hit tool and excellent instincts on both sides of the ball. The A's will probably send him right to High-A Stockton, a level more appropriate for his age and experience.
Overall, it's a solid return for two relievers who didn't fit the A's payroll structure and who carry the health and performance risk common to all relief pitchers.