Whiteside will miss the Heat's home game Wednesday against Brooklyn after the talented but emotional center was ejected for the second time in as many weeks.
The hit on Olynyk came late in the third quarter, when Whiteside took exception to physical play between the two earlier in the game. Whiteside initially swung his elbow upward to prevent Olynyk from grabbing his arm and moments later followed Olynyk down the lane and shoved a forearm into the back of his neck.
Whiteside was initially assessed a personal foul, but the call was upgraded to a Flagrant 2, which warranted an automatic ejection from the game. Heat teammates, including Dwyane Wade, condemned Whiteside's actions, questioned his maturity and challenged him to be more reliable.
After Tuesday's practice, Whiteside said he reached out to apologize to Olynyk and vowed to do a better job of keeping his emotions in check on the court.
"I feel terrible about it. I feel like I let my teammates down," said Whiteside, who finished with seven points and nine rebounds in 22 minutes. "It can't happen again. I just want to apologize to everybody."
Losing Whiteside for any length of time is costly for the Heat, who are in ninth place in the Eastern Conference and fighting for one of the final playoff spots with 19 games remaining.
Whiteside also was ejected in the second half of a March 2 home win against Phoenix for his role in an altercation with Suns center Alex Len. The league ruled that Len initiated the altercation but that Whiteside escalated matters when he lunged and grabbed at Len's knees as the two fell out of bounds.
The 25-year-old Whiteside was fined $15,000 for that incident last week and has already paid $40,000 in league disciplinary fines, with a recent string of technical fouls and skirmishes on the court overshadowing his standout production for the Heat.
"We all have our moments -- selfish moments -- but you can't continue to keep having them," Wade said of Whiteside after Monday's game. "You've got to be reliable, and you've got to be able to be counted on. And right now, if he continues to act that way, then he's not reliable."
Whiteside's emergence from a D-League prospect who also had several stints playing overseas has been one of the more surprising developments in the league this season. He has four games with at least 20 rebounds and finished with 14 points, 13 rebounds and 12 blocks in a Jan. 25 win in Chicago.
But maintaining his temper has been a problem at times for Whiteside, who is averaging 13.3 points, 13.3 rebounds and 2.4 blocks in his last 10 games but has seen his playing time limited recently because of foul trouble. Still, the Heat have had to rely heavily on Whiteside this season because of a rash of injuries, including season-ending setbacks to forwards Chris Bosh and Josh McRoberts.
"We're not turning our back on Hassan; he's a family member," Heat coach Erik Spoelstra said Tuesday. "We're going to correct this with him and move forward. He understands how his actions affect the team. He wants to help us and be a part of this."