By Zach Koons The Olympic gold medalist is coming off of a breakout 2021–22 season in San Antonio. View the original article to see embedded media. Spurs forward Keldon Johnson has agreed to a four-year, $80 million extension with the franchise, as first reported by Shams Charania of The Athletic. Johnson, a three-year NBA veteran, will sign the deal following a breakout season in San Antonio. In 75 games during the 2021–22 campaign, all of which he started, the 22-year-old averaged career-highs in points (17.0), rebounds (6.1) and assists (2.1). He also shot 39.8% from three-point range, prov…