What's surprising is the fact that it was not a player who cost the Heat this matchup. Instead, it was a grave mistake by head coach Erik Spoelstra in the dying seconds of the game.

Erik Spoelstra uncharacteristically called a timeout with none remaining which led to a loss in Miami's first NBA Cup game of the season.

Erik Spoelstra, who is widely known as one of the NBA's top coaches, shouldered blame for a brutal timeout infraction, calling it a "serious mental error" in the final seconds of a Miami Heat loss to the Detroit Pistons.

Miami Heat head coach Erik Spoelstra admitted that his own “horrendous mistake” cost the team in its 123-121 defeat to the Detroit Pistons in the NBA Cup on Tuesday.

Spoelstra was assessed a technical foul, and Pistons guard Malik Beasley sank the ensuing free throw, giving Detroit a late lead the club would not relinquish. After the game, Spoelstra took accountability for the mistake that led to Detroit's victory.

That last game was particularly interesting because it involved one of the greatest coaches of this generation making an incredibly uncharacteristic mistake at the worst possible time. With the game tied at the end of the extra period, Erik Spoelstra called a timeout … even though the Heat didn’t have any.

The sample size is very small, but Erik Spoelstra might have made the biggest coaching blunder in NBA Cup history on Tuesday. The Heat inexplicably allowed four points in the final 1.8 seconds of overtime on the Pistons' bright blue court,

Erik Spoelstra made a critical error that contributed to the Miami Heat’s loss against the Detroit Pistons in their NBA Cup opener. Following the game, team leaders ...

Tyler Herro had the most outstanding performance of the season. It was ruined by Erik Spoelstra’s mistake by calling a timeout when the team had none.

Miami Heat head coach Erik Spoelstra did not hold back when speaking about his costly last-second decision after the Pistons loss.