His brother Phil was already a star pitcher for the Braves when Joe Niekro drafted in the third round by the Cubs in 1966. In his rookie season in Chicago (1967), Joe won 10 games.

He won 14 games for the Cubs in 1968, but manager Leo Durocher, never very good with young players, seemed to lose faith in him. Leo wasn't alone in that assessment. Niekro's ERA was a little high (for that pitchers era) at 4.32, he was far from overpowering (only 65 strikeouts in 177 innings), and his control was a little shaky. When the Cubs had a chance to get veteran Dick Selma early in the 1969 season, they didn't hesitate to include Joe Niekro in the deal.

Selma won ten games for the Cubs that season, and really connected with the Bleacher Bums. It looked like the Cubs had made a pretty good deal, even though Selma was traded away the following season. Niekro bounced around the bullpens of Detroit and Atlanta for awhile, never really making much of a name for himself. But while he was with the Braves, he finally perfected the knuckleball that had been the secret to his brother's success, and his career really took off.

The Astros put him in their rotation in 1977, and for the next eight seasons he averaged more than 15 wins a year, including back-to-back 20 win seasons in 1979 and 1980.

By the time his career was over after the 1988 season, Joe Niekro had 221 career victories. Only 24 of those came for the team that drafted him and brought him to the majors; the Chicago Cubs.