The Los Angeles Dodgers' signing of Edwin Diaz to a record-breaking contract (in terms of AAV) is sure to have numerous ramifications on MLB in 2026 and beyond, as the two-time reigning champions now have one of the best closers in baseball ready to join forces with an elite rotation and lineup.
The Boston Red Sox were never going to be in his market, thanks to the presence of their own star closer Aroldis Chapman. During the middle of a (re)breakout campaign in 2025, the flamethrowing southpaw signed a one-year, $13.3 million extension to remain in Beantown for an additional season.
Considering that the Dodgers just spent $69 million on Diaz — who had comparable stats to Chapman this past season — it's safe to say the Red Sox were wise to lock up their closer when they did.
Diaz is an excellent relief pitcher, and his advantage in terms of age — he'll be 32 on Opening Day, whereas Chapman will be 38 — makes it clear why he received a lucrative multi-year deal from the deepest-pocketed team in the sport. But is he so much better than Chapman that he was worth an additional $56 million over the 2027 and 2028 seasons? The stats certainly don't support such a conclusion.
MLB relief market proves Red Sox were right in extending Aroldis Chapman
Edwin Diaz v. Aroldis Chapman, 2025 performance
Diaz: 1.63 ERA, 2.28 FIP, 28 saves, 38.0% strikeout rate, 2.0 fWAR
Chapman: 1.17 ERA, 1.73 FIP, 32 saves, 37.3% strikeout rate, 2.6 fWAR
Notably, Diaz has been known for oscillating between elite and middling performances. Since making his MLB debut in 2016, his ERA has been below 3.00 in every even-numbered year, and above 3.00 in every odd-numbered year (the trend reversed after he missed the 2023 season due to injury). That's a lot of money for someone who has been reliably unreliable about half the time.
Of course, Chapman has his own issues, and there are reasons to be concerned about a 38-year-old pitcher who relies on a triple-digit fastball. Father Time will catch up with him eventually, which is why it was prudent of the Red Sox to limit his extension to one year (with a vesting option for 2027).
Considering the money other, non-elite relievers are getting this winter, it's clear that Chapman's contract is a bargain. Kyle Finnegan got nearly $20 million over two years with the Detroit Tigers; heck, even former Red Sox reliever Steven Matz got more guaranteed money than Chapman from the Tampa Bay Rays.
Whether because of his distaste for the New York Yankees or his love of Boston, Chapman settling for a below-market deal is proving to be a boon for the Red Sox this offseason.