The singer, who performed at the event, was spotted still wearing the ring that looks suspiciously like engagement bling.
Miley and her The Hunger Games star boyfriend were joined by Tom Hanks, Rita Wilson, Reba McEntire, Billy Crystal and many other fans of the legendary boxer, for the annual bash that raises millions for the Muhammad Ali Parkinson's Center at St. Joseph's Hospital in Phoenix.
As RadarOnline.com previously reported, Miley started the engagement guessing game when she tweeted a photo of her left hand, commenting on her manicure, but distinctively showing off the ring.
The Hunger Games opened this weekend and is expected to take it as least $135 million in its first three days.
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