2. Rick Reuschel 48.3 WAR with the Cubs
Known by the affectionate nickname "Big Daddy" for his rotund body, Rick Reuschel was one of the mainstays in the Cubs' rotation throughout the 1970s. He began his professional career when the Cubs drafted him in the 3rd round of the 1970 draft, and he found his way to the big league team in 1972. Reuschel was a horse for Chicago, compiling 8 straight seasons with the Cubs where he threw 230+ innings, and his career ERA with the team was 3.50.
He also threw 65 complete games for the team, and 17 of them were shutouts. Reuschel's 12 years with Chicago have solidified him as sixth in franchise history in innings pitched with 2290. That record will likely stand for a long time unless Kyle Hendricks signs another long-term deal with the team since he is the only one that is relatively close to reaching Reuschel's IP heights with 1341 as of this writing.