[3] Cox graduated from Alamo Heights in 1966 and attended Odessa Junior College and then Trinity University.

Amateur he shot a 65 at Portland's Waverly Country Club to tie for the lowest 18-hole score in the history of the event.

[4] Shortly thereafter, Cox won the Greater San Antonio Men's Championship in 1971 and 1972 while still an amateur.

Among the 81 competitors Cox finished in a tie for 21st, defeating several future PGA Tour pros.

The following year he qualified for his first major championship, the 1973 U.S. Open at Oakmont Country Club.

He shot a 74 in the first round at Medinah Country Club to put himself inside the cut line.

[9] Rather, Cox played events in the Asia-Pacific region for most of his regular career as a touring professional.

[10] The following year, he played well at West Lakes Classic held at The Grange Club in Adelaide, Australia.

Cox shot a final round 71 (−1) to finish in a tie for third, three back of champion Walter Godfrey.

In March 1980, Cox won the Indian Open, held at Royal Calcutta Golf Club, where he finished four strokes clear of Taiwan's Liao Kuo-chih and Burma's Mya Aye.

[15] The victory put him atop the Asia Golf Circuit's Order of Merit standings.

[18] He finished the 1980 season as runner-up in the final standings, behind Taiwan's Lu Hsi-chuen.

[20] Later in the year he played in two regular PGA Tour events, making the cut in both.

In the third round he shot a 70 (E) to match the aggregate totals of Tom Sieckmann and Terry Gale to tie for the lead.

[21] Sunday was a back and forth day as the three players traded the lead throughout the final round.

On the final green, Cox had a chance to win but missed a two-yard birdie putt, forcing a sudden-death playoff.

[23] In December 1983 Cox played the PGA Tour Qualifying Tournament at TPC Sawgrass.

[1] In his career Cox recorded an ace at the par-4 17th hole at Brackenridge Park Golf Course in his hometown of San Antonio.

[2][8] Cox met his future wife a club pro shop in Kuala Lumpur, Malaysia during his experiences on the Asian circuit.