"Coach wants me to just be in a corner and set picks," Whiteside said, per Tim Reynolds of the Associated Press.
The center finished with five points and two rebounds in 13 minutes in the 128-108 home loss to the Philadelphia 76ers in Game 3.
Whiteside averaged 14.0 points and 11.4 rebounds per game this season, but he only has 11 points and 12 rebounds over the first three games of the series combined. He has struggled with foul trouble, and he hasn't played more than 15 minutes in any contest.
Charles Barkley of TNT had some harsh criticism of the 28-year-old:
"They are better without him. It's plain and simple," he said of Whiteside.
Meanwhile, Joel Embiid was dominant for the 76ers in his return from an orbital bone injury, finishing with 23 points and seven rebounds.
As a result of this one-sided matchup, Philadelphia owns a 2-1 series lead.
Whiteside signed a four-year, $98 million contract in 2016 and responded last season by leading the NBA with 14.1 rebounds per game and setting a career high with 17.0 points per contest. Unfortunately, he hasn't been that type of player in 2017-18, and especially not so far in the postseason.
If he and Spoelstra can't figure things out, the Heat are in trouble for the series, and there could be some personnel changes in the offseason.