Bob Bass, a two-time NBA Executive of the Year who spent 20 seasons with the San Antonio Spurs and also served as general manager of the Charlotte Hornets, died Friday night at the age of 89, the teams announced.

Blair Bass-Percle, a granddaughter, told mysanantonio.com that Bass had suffered two strokes since Aug. 6.

After coaching in the ABA and in college at Oklahoma Baptist and Texas Tech, Bass joined the Spurs in 1974 and served as head coach until the ABA-NBA merger in 1976. He then joined the team's front office, helping build the foundation for the team's success while serving as general manager, vice president and assistant to the chairman.

"Over the course of four decades, Bob Bass had a huge impact in both the ABA and NBA," Spurs coach Gregg Popovich said in a statement released by the team Saturday. "BB was a true pioneer in the world of professional basketball. His knowledge, passion and dedication to the game were inspiring. We send our condolences to the entire Bass family."

Bass left the Spurs in 1994 and was hired as the general manager of the Hornets, who never had a losing season in his nine seasons. He retired in 2004.

"After coming to Charlotte in 1995, Bob was responsible for some of the most successful teams in Hornets history and left an indelible mark on our franchise," the Hornets said in a statement.

Our deepest condolences go out to the family and friends of former-Hornets GM Bob Bass, who passed away yesterday at age 89. Bass spent seven seasons in Charlotte and was named the 1997 NBA Executive of the Year. pic.twitter.com/bpHjBAx23u — Charlotte Hornets (@hornets) August 18, 2018

In addition to the Spurs, Bass also coached the Denver Rockets, Miami Floridians and the Memphis Tams of the ABA and had a professional career record of 311-300.