Pat Riley expects a fun July in Miami, and his plan starts with getting on the right side with center Hassan Whiteside. "He's a game-changer," Riley said. "I don't even think he's reached his real ceiling."The Heat enter a transition offseason with questions about their biggest and best. Dwyane Wade will be a free agent, but Riley said he talked to Wade and both sides are eager to stick together. Chris Bosh, who has $75 million on his contract but missed 81 games the past two seasons due to blood clots, is a major X-factor.Whiteside's contract is the matter of utmost importance to the Heat, Riley said."Your offense is only as good as what you do at the defensive end," Riley said. "... That's why Hassan is so important to us in a lot of ways. He'll block shots, he'll rebound the ball, he'll change 10 other shots, he'll scare the hell out of about four or five other people coming into the paint and he's got some intangibles that simply you just can't find."Whiteside was there for the taking by all 30 NBA teams and went to China and Lebanon to get professional work. With the Heat last season, he made $981,000, a figure that could rise to more than $12 million per season when free agency begins July 1.What else the Heat might be able to add depends largely on Bosh.His contract would only come off the books if he's traded or forced into medical retirement, in which case the deal isn't erased until February, a calendar year after his last game. Bosh said last week retirement was not currently a consideration. Riley sounded optimistic but cautiously so."Not just the Heat but the doctors and also Chris are looking to proceed forward to find a way to get him back on the court," Riley said. "I think that's all we can say right now. We are very encouraged by trying to find a way over the next two or three months to find a protocol and a program that will get him back playing. That's always been our objective. We're in this together," Riley said, echoing the words of coach Erik Spoelstra following the Game 7 conference semifinals loss in Toronto last week. Last summer, the Heat convinced point guard Goran Dragic to stay in Miami for less money than he could have earned elsewhere. Dragic said he's ready to lead the recruiting pitch to keep Whiteside, who averaged a double-double in 2015-16."He was unbelievable this season. He was great for this team. Hopefully, he sees that everybody likes him here. I love playing with him," Dragic said, joking that he would need to create a Snapchat account to keep in contact with Whiteside. "Of course, we want him back ... hopefully he stays."