Carlos Cleckley, who formerly coached at Beaver Falls High School, pleaded guilty on Thursday to the federal charges.
That makes Cleckley the third of four defendants to plead guilty in the case.
Authorities busted the ring in 2011, seizing a 16-kilogram shipment of cocaine from Texas and $669,000.
Thirty-six-year-old Adrian Taylor, of Beaver Falls, and the alleged supplier, 39-year-old Vincent D. Middlebrooks, of Houston, have already pleaded guilty. Authorities say the ring was responsible for most of the cocaine sold in Beaver County, just northwest of Pittsburgh.
A fourth defendant still plans to stand trial.