I think the saber community underrates Brown a bit. See there was a strategy managers use to do called leveraging. Managers would try to get as many starts from their best pitchers against the best teams. Then they would use their mediocre pitchers against the teams lower in the standings.
Brown’s manager Frank Chance did this as much as anyone in Chris Jaffe’s book “Evaluating Baseball’s Managers” which I talked about before. The man that Chance did this with is Three Finger Brown. One year there was only 2 teams over .500 along with Brown’s Cubs, leaving 5 teams below .500. Yet Brown pitched over half his starts against the two .500 teams. Other pitchers would pitch almost all their starts against the 5 teams below .500.
Another thing was this pitching rotation, he often ended up matched against Christy Mathewson, the best pitcher of the first decade of the 20th century. He held his own with Christy actually winning more than he lost.
Brown is also unique due to having a missing finger. It gave the balls he threw natural movement. Remember Brown wasn’t one of my top 183 players, he is one of my 12 additional pitchers. Well one thing about Brown that is unique is the pitching hand he got. It is an interesting story. Part of his index finger was lost to a piece of farm equipment. It happens to farmers. My Father told me about a relative of his that lost his life to a piece of farm equipment he was trying to fix while out in the field. Later in childhood, Brown bent his middle finger and broke other fingers on his hand chasing a rabbit. So, his hands were all messed up, but it made him pitch better.
Another thing that hurts Brown’s rating was he had a fairly short career. He pitched in the majors for only 14 years. He did pitch until age 39. However, he didn’t pitch in the majors until he was 26. His Saber biography mentions only two years in other leagues. Baseball Reference has no minor league stats. So, he either played and was on nobodies radar or wasn’t playing organized baseball anywhere.
Another thing that Chance did more and more in Brown’s career was use him in relief of his other pitchers in close games. Starting in 1908 he led the league in save four years in a row. Chance was easy on his starters starting Brown on average every fifth game which was less than usual. Chance in those championship years of 1906 to 1908 had five- or six-man staff. Brown usually led or was second in starts. However, he pitched a lot in relief. More as the championship years went away.
Brown broke the save record in 1911 with 13. Of course, now that amount is very low for a relief ace. However, when he held the record with Chief Bender when he retired. He also had the career save record (with 49) when he retired. However, nobody knew this as saves weren’t invented at this time. Firpo Marberry broke both of these records in the 1920s.