The announcement was made on Monday.
Since retiring at the end of the 2015-16 season, Duncan had been spotted on occasions practicing with the Spurs players at the team's facility.
Duncan, 43, played 19 seasons with the Spurs and won five National Basketball Association championships playing for Popovich from 1997-2016.
Hardy has served as the head coach of the Spurs' Summer League team in Utah and at one point, appeared as the head coach of the Spurs' 2017 Spurs MGM Resorts Summer League team.
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Defense Lawyer Yaniv Habari told the Israeli Haaretz newspaper that he met with his clients and "they're in a good mood". The Times of Israel said some of the men involved in the alleged attack were minors, and that the alleged victim was 19.
Duncan is a 15-time NBA All-Star, was the Rookie of the Year in 1998, is a two-time NBA MVP and 15-time All-Defensive Team player.
The prevailing wisdom at the time was that Pop would continue coaching the Spurs until at least the 2020 Olympics, but there was no guarantee he would return until he signed a three-year contract extension.
Hiring Tim Duncan as the next head coach would certainly win the press conference in San Antonio, and we know that this organization loves to hire within to maintain their historically great culture.
Duncan and Spurs video coordinator Will Hardy will join Chip Engelland and Becky Hammon on the bench alongside Popovich. Will Hardy also has been elevated to assistant coach.