In 1970, after spending the season in the minor leagues with the Iowa Oaks of the American Association, Blue was called up in September and made two starts that provided a glimpse of what was to come for the 21-year old. On September 11, he shut out the Kansas City Royals 3-0, giving up only one hit, to Pat Kelly in the eighth inning. Ten days later, he no-hit the Minnesota Twins, 6-0, at Oakland-Alameda County Coliseum. The lone baserunner came on Harmon Killebrew's fourth-inning walk. The no-hitter capped a season that witnessed four no-hitters.