https://en.wikipedia.org/wiki/Jack_M...y_(basketball)
McKinney took the helm of the Lakers for the 1979-80 NBA season, but only 14 games into the season, he suffered a near fatal head injury after falling while bicycling. His assistant, Paul Westhead, was named as the team's interim head coach while McKinney tended to recovering from his accident. However, the length of the recovery and lingering doubts about the complete return of McKinney's mental faculties, combined with the team's level of success under Westhead, ultimately meant that McKinney would never get the chance to return to the job. After the Lakers advanced to that year's NBA Finals, Westhead permanently replaced McKinney and the team went on to win the 1980 NBA Championship.
McKinney went on to win the NBA Coach of the Year Award the next season at Indiana, leading the Pacers to the playoffs for the first time since the ABA-NBA merger brought the team from the American Basketball Association to the NBA in the summer of 1976.