What record we have of Mendez is not too helpful to his Hall of Fame argument. His won-loss is but not his ERA. The main problem is we have the record only when Mendez is 35 to 41 years old, after pitching from years in Cuba. I’m sure this isn’t his prime. Another is the short seasons just look bad until you realize there isn’t enough evidence there to tell you much of anything. His SABR biography says his arm was basically dead at this time.
His SABR biography has him at 9-11 against American teams that came to Cuba in the late decade of the 1900s and early 1910s. The biographer has a concern about this because this was a big part of why he was elected, the legend of these games. However, most of those games were against quality teams. Except for 3 games against the Cincinnati Reds and one against Brooklyn his three opponents were the Detroit Tigers in 1909 and 1910. They won the pennant in 1909. This team also had Ty Cobb and Sam Crawford two great Hall of Famers. Then he faced the Philadelphia A’s and New York Giants the two dominate teams of the early 1910s. Sorry three of those games were against the Phillies so not as strong as I thought.
As hinted at in the paragraph above Mendez’s biographer questions whether Mendez should have been elected as his legend might be overblown. This is interesting as the usual SABR article will argue only the positives about a player. I admire the author for taking this tack and it makes for interesting reading.
However, there is the following is his favorite. He pitched against major league teams and was basically a .500 pitcher against them with a lot of raw talent behind him. Coming to the Negro Leagues as an old pitcher with a history of arm trouble he more than held his own. His Baseball Reference WAR winning percentage is .675 which is certainly Hall of Fame worthy, with the only qualification being a short career.
His biographer says he lost a lot on his fastball after the early years due to injuries and was only great a short time. All before coming into the Negro Leagues. I say even though he had a short peak he was a solid pitcher after that for a good number of years and support his Hall of Fame election.