The Bieb was definitely the star of the night, winning three awards at the Canadian event. However Miley held her ground as the show's host and featured performer. She sang two songs that evening, including 'Can't Be Tamed' and her 2009 hit 'Party in the U.S.A.,' during which Justin made his cameo.
Although the 16-year-old pop singer didn't hit grab the mic, he did lend his support as a bandana-wearing dancer who rolled up to the front of the stage on a low rider bike. Naturally, when Miley revealed who her mystery guest was, the crow went wild. Miss out on the MMVA action? Watch the entire high-energy performance of 'Party in the U.S.A.' after the jump.