On March 24, 1958, Cokes began to box professionally, defeating Manuel Gonzalez, whom he would later fight for the world title, in a six-round decision. He won eleven fights in a row, including a second match with Gonzalez, before losing to Gonzalez in their third fight, on April 27, 1959. His next fight, against Garland Randall on June 18 of the same year, ended in a three-round no contest. He and Randall had an immediate rematch and on August 27, he knocked out Randall in the first round. He had an additional fourteen fights, going 11-2-1 in that span (his one draw was against Kenny Lane, a boxer who twice challenged Carlos Ortiz for world championships), before facing Luis Rodriguez, another world welterweight champion, on September 3, 1961. He beat Rodriguez by a ten-round decision, outpointed Gonzalez in their fourth fight, and lost to Rodriguez in their second fight, also by points. He went 13–4 in his next seventeen fights, and, after losing in a ten-round decision to Eddie Pace at Los Angeles, California, on August 27, 1964, he announced his retirement. However, on October 14 of that year, he announced he was returning to boxing.
Championship
After winning three fights in a row, he and Gonzalez were matched for a fifth time on August 24, 1966, this time for the WBA/WBC vacant world welterweight title, in New Orleans. Cokes outpointed Manuel Gonzalez to become world welterweight champion. On November 28, 1966, he retained the crown against Jean Josselin of France in a fifteen-round decision. Nat Fleischer was one of the judges for that fight.
On May 19, 1967, he retained the title with a tenth-round knockout of Francois Villeiman, and on October 2, he met Charlie Shipes, who was recognized as champion in California. He knocked Shipes out in eight rounds in Oakland.
On April 18, 1968, he retained his title with a fifth-round knockout of Willie Ludick, and on October 21, with a fifteen-round decision over Ramon La Cruz.
Post-championship career
Cokes lost the world welterweight title on April 18, 1969, when he was knocked out by Cuban José Nápoles in thirteen rounds in Los Angeles. On June 29, the pair had a rematch in Nápoles' adopted hometown of Mexico City, Mexico, and Nápoles repeated his victory, this time by a tenth-round knockout.
Cokes had eleven more fights before retiring, winning seven, losing three and drawing in one. His last three fights were in South Africa. He retired after a ten-round decision win against Ezra Mnzinyane on October 5, 1972.
Cokes had a record of 62 wins, 14 losses and four draws, with 30 wins by knockout.
After boxing
After retiring, Cokes became a trainer. He worked with fighters such as Quincy Taylor and Ike Ibeabuchi.
