NBA career
Walker was selected #1 overall pick in the 1967 NBA draft by the Detroit Pistons. He was also drafted #1 overall in the inaugural American Basketball Association Draft by the Indiana Pacers. 1967 was the first year the NBA had abandoned its territorial draft (under the old draft, which granted an extra first-round pick to be used on collegians within 100 miles of their professional team, Walker might have been selected by the Celtics and teamed with his mentor Sam Jones). Walker was also the final pick in the 1967 NFL draft by the New Orleans Saints (the pick now known as Mr. Irrelevant), despite never having played college football; this makes Walker the only athlete drafted first by one pro league (two in his case) and last by another.
In the middle of the 1968–69 season, Walker was nearly traded to the New York Knicks for Walt Bellamy, but the firing of Donnie Butcher for Paul Seymour meant that he nixed the trade and instead wanted Dave DeBusschere traded to New York for Bellamy, which was accepted.
Despite playing in two NBA All-Star games, Walker never reached his full potential as a pro, partly due to his weight gain. His game had been predicated on quickness. Nonetheless, he averaged 20.9 ppg in 1969–70, 21.3 in 1971–72, and 19.8 in 1973–74, averaging almost 17 per game over a 9-year career. The numbers are all the more impressive when one considers that Walker teamed with star guards such as Dave Bing in Detroit, and Nate Archibald in Kansas City-Omaha.
Overall in 698 games with the Detroit Pistons (1967–1972), Houston Rockets (1972–1973), and Kansas City Kings (1973–1976), Walker averaged 16.7 points, 2.7 rebounds, and 3.5 assists in his NBA career.
