Miami Heat president Pat Riley says his team needs to have an "intervention" with Hassan Whiteside before the start of next season.

"There has to be an intervention and I'm going to be the intervener," Riley said at his end-of-season availability, indicating he wasn't interested in dealing the centre. "That's real. You got a guy that's second or third in starting centers in plus/minus. There's no doubt he was in a bad state in the playoffs. Whatever the reasons why, I have not really sat down with [coach Erik Spoelstra] and really talked about all of these things. Hassan was less-than, without a doubt, in the playoffs."

Whiteside, 28, was a shell of his regular season form during the Heat's six-game series loss to the Philadelphia 76ers.

Over 54 games this season, Whiteside averaged 14.0 points and 11.4 rebounds over 25.3 minutes a night. In the playoffs, Whiteside's minutes were limited to 15.4 a game, while he only contributed 5.2 points and 6.0 boards. Much of that was due to Spoelstra monitoring Whiteside's minutes over a series of lower-body issues afflicting him over the season that resulted him in missing 28 games.

"By the time we got to the playoffs, I don't think he was ready," Riley said of Whiteside. "He wasn't ready. He wasn't in great shape. He wasn't fully conditioned for a playoff battle mentally. He and we got our heads handed to us."

Riley says that it's incumbent on Whiteside to adjust with the new expectations placed on frontcourt players in the modern NBA.

"That problem is that he's going to have to do something to change because he's a helluva player," Riley said of getting Whiteside. "You've got [Steven] Adams. You've got [Clint] Capela. You got [Jonas] Valanciunas. You got DeAndre Jordan. You've got [Andre] Drummond. You've got Hassan. You've got these quintessential sort of centres that are being forced to play a certain game because the game has changed and there's only one or two or three teams that can play that game, because three or four transformative players that can make that game effective. So, how do we make him effective?"

Whiteside has one year and a player option left on a four-year deal signed in 2016 worth just over $98 million.