2026 Fantasy Baseball Closer Rankings: Mason Miller vs. Edwin Díaz for RP1

Mason Miller vs. Edwin Díaz headlines the 2026 fantasy baseball closer rankings, with elite strikeout rates, evolving save roles, and top-30 NFBC price tags.

San Diego Padres relief pitcher Mason Miller (22) celebrates during the eighth inning Arizona Diamondbacks at Petco Park. | David Frerker-Imagn Images

The race to be the first reliever drafted in 2026 fantasy baseball comes down to Mason Miller’s unmatched strikeout upside and Edwin Díaz’s elite ratios on a loaded Dodgers roster. Understanding their roles, save share, and command trends is the key to deciding whether to pay a top-30 price for an anchor closer.

RP1 – Mason Miller, San Diego Padres (NFBC ADP – 27)

Miller will be the top closer drafted in many leagues in 2026, but he cost fantasy drafters twice last season. The first came over a dismal six-game stretch in May (10 runs, 17 baserunners, two home runs, and 12 strikeouts over 5.2 innings), leading to two losses and two blown saves in three chances. The second issue was a surprising trade to the Padres, turning him into a setup man and crushing his playable fantasy value for saves (2).

His season opened with an electric run over 12 games (1.50 ERA, 0.667 WHIP, and 23 strikeouts over 12.0 innings) when Miller converted all 10 of his saves. After his May slump, he converted 10 of his next 12 save tries, with a stellar ERA (1.29) and WHIP (0.714) with 67 strikeouts over 42.0 innings. His season ended with 21.1 consecutive shutout innings with 42 strikeouts.

His average fastball (101.2 mph) ranks among the top of the league in velocity, and he threw it 51.7% of the time. Batter struggled with his four-seamer (.162 with 52 strikeouts) and his slider (.104 BAA with 59 strikeouts). Miller threw a changeup only 22 times, resulting in one hit and one strikeout.

Despite his success in 2025, the Padres’ top reliever only threw 57.4% first-pitch strikes, resulting in a losing walk rate (4.1). His ceiling would be over the chart if Miller upped his success to 65% or higher. Despite his command issues, he finished with his highest strikeout rate (15.2 – 17.4 with the Padres) in his career. Almost half of right-handed batters struck out against him (65 Ks over 132 plate appearances).

Mason Miller 2026 Fantasy Baseball Outlook

Fantasy Outlook: His split closing role last year led to Miller ranking 16th in FPGscore (-0.10) for relief pitchers. If he finished with 40 saves, his rating would move to +3.74 (4th). Miller should also get more wins in San Diego (one in 2025 and three in his career). With 70 appearances, I could see 125 strikeouts with dominating stats in ERA, WHIP, and saves. Last year, the Padres’ relievers had 49 saves and 44 wins.

RP2 – Edwin Diaz, Los Angeles Dodgers (NFBC ADP – 30)

Los Angeles Dodgers pitcher Edwin Diaz (3) throws in the bullpen during spring training camp. | Rick Scuteri-Imagn Images

The Dodgers swooped in and signed Diaz to a three-year, $69 million deal, a year after ponying up $72 million for Tanner Scott. He comes off his fourth season in his career with a sub-2.00 ERA. In three of these years, Diaz showed better command (2.1, 2.6, and 2.8 walks per nine) while maintaining an edge strikeout rate (13.3 – 14.5 in his career).

The Mets’ relievers had 40 saves last season, with Diaz converting 70% of them. Despite his rebound in command, he had a sharp decline in his first-pitch strike rate (55.2%), compared to a career-best 71.1% in 2022 (61.9% in 2024).

Diaz struggled in back-to-back games (five runs, seven baserunners, and one home run over 1.2 innings) in April, with a down month in August (four runs, 11 baserunners, and two home runs over 9.0 innings with 15 strikeouts). He had an electric 17-game run between June and July (no runs, 13 baserunners, and 25 strikeouts over 17.1 innings).

His average fastball (97.3 mph) remains an edge. Diaz relies on two elite pitches (four-seamer – .128 BAA and slider – .172 BAA with 59 strikeouts). He had similar success against right (.171 BAA) and left (.158 BAA) batters.

Edwin Diaz 2026 Fantasy Baseball Outlook

Fantasy Outlook: Diaz was the second-best reliever in 2025 based on his FPGscore (3.95). Last year, the Dodgers’ bullpen had 45 saves, which were divided up by 12 pitchers. Los Angeles would love to have two arms secure most of their closing chances this year. I expect Tanner Scott to get about one-third of their chance, suggesting a 35-save ceiling for Diaz. Great arm, pitching for the best MLB roster, setting the stage for his best overall season since 2018.

Mason Miller vs. Edwin Diaz 2026 Fantasy Baseball Verdict

Miller has the highest ceiling in the player pool if he regains a full-time ninth-inning role in San Diego, with 40-save and 125-strikeout upside that can swing entire leagues. Díaz offers a safer ratio floor and win potential in Los Angeles, but a split save situation slightly caps his overall return at cost. Miller is the superior option.