5. Bill Plummer (-3.6 WAR)
Plummer may be one of the most interesting cases on one of these. Never much of a hitter, he played for the Reds from 1970 to 1977 without amassing an OPS above .700 or over 160 AB in a season. How did he play for the Reds that long? Even the Big Red Machine had a backup catcher.
4. William McKinley "Max" Venable (0.9 WAR)
Venable spent 3 seasons in the Reds outfield, from 1985 to 1987. He played mostly in a bench role here, but could play all around the outfield.
3. Ray Lamanno (2.0 WAR)
A catcher by trade, Lamanno wore #9 for the Reds in 1941 and 1942 before heading to fight. He finished 27th in the MVP race in 1942, hitting .264/.324/.404 in an era where you could get MVP votes by OPSing .728. It was by far his best season.
2. Lew Riggs (5.1 WAR)
Riggs played 3B for the Reds, and wore the number between 1935 and 1937. He made his only All-Star appearance in 1936, and played for the Reds in other numbers until 1940.
1. Joe Oliver (3.3 WAR)
I don't remember Lew Riggs or Lamanno, or even Venable wearing #9. I remember Joe Oliver. Joe wore the number from when he broke into the league in 1989, all the way to 1994, and again in 1996 before switching to #7 in 1997. He made the bulk of the starts at catcher in the 1990 season, and that seems pretty darn important to me.