Mariano Rivera is 40 years old, still pitching extremely well, and is first in baseball history in ERA+. Among active pitchers, he’s ranked first in ERA, WHIP, H/9IP, K/BB, HR/9IP, WPA, and fielding percentage. (Go ahead and carefully re-read that last sentence.)
He’s an 11-time All-Star, finished in the top five for the Cy Young five times, and received MVP votes in nine different seasons.
He’s also the career leader in postseason ERA (despite having more IP than every other pitcher in the top 10) and has been a part of five World Series championship teams.
Bleacher Report - New York Yankees