MLB Network finished their rankings of the top 10 players at each position in baseball with their revealing of the best shortstops and relievers last night.
The only relievers that appeared on the list ahead of him were Craig Kimbrel, Sean Doolittle, and Josh Hader. Behind Diaz were Blake Treinen, Felipe Vazquez, Chad Green, Aroldis Chapman, Jose Leclerc, and Brandon Morrow in that order.
Diaz, 24, had a career year in 2018 in which he registered a 1.96 ERA, 0.79 WHIP, 1.61 FIP, and 124 strikeouts in 73 1/3 innings pitched while notching an MLB-leading 57 saves.
Meanwhile, the Washington Nationals had Sean Doolittle ranked second on the list, but also saw two former members of their team end up ranked on the list in Treinen and Vazquez.
The number one pitcher on this list, Craig Kimbrel, is still sitting out on the free agent market looking for his new home or for the Boston Red Sox to resign him. The Atlanta Braves and Philadelphia Phillies have also both shown varying degrees of interest in signing Kimbrel this offseason.
As of today, the Mets are expected to enter the season with Diaz, Jeurys Familia, Justin Wilson, Seth Lugo, and Robert Gsellman with some combination of Drew Smith, Luis Avilan, Kyle Dowdy, Hector Santiago, Tyler Bashlor, Jacob Rhame, and Paul Sewald occupying the last two or three spots in the bullpen to start the season.