The Jonas Brothers kicked off their world tour on Saturday in Dallas at the Cowboys Stadium, and it seems like the guys pulled out all the stops to keep the crowd of nearly 50,000 entertained.

According to reports, the JoBros played songs both old and new, including cuts from their new album, Lines, Vines and Trying Times, which was just released last week. But the performance of one new song in particular really drove the crowd wild.

For "Before the Storm," a duet between Nick Jonas and Miley Cyrus from Lines ..., Nick was joined onstage by none other than Cyrus. The performance comes amid recent rumblings — including statements from Miley and Nick's older brother, Joe — that the teens have started dating again. Nick strummed the acoustic guitar while Miley, dressed in a white dress and boots, hit the stage with her on-again, off-again beau.





Miley And The JoBros Perform In Dallas

A couple of weeks back, Joe Jonas had hinted to MTV News that there was a possibility that fans would get a chance to see Miley perform the track with them live.

Earlier that evening, Miley actually gave a clue about the appearance on Twitter. "In one of my favorite cities with my favorite people," she wrote. "Guess where I am and what I'm doing. I will never tell :)" She then followed up the Tweet post-show, writing, "@mileycyrus had an awesome time with @jonasbrothers last night. The show was awesome :) I miss you already :(" She also Tweeted Heidi Montag, saying, "He's amazing."

The guys thanked Miley via Twitter as well, writing, "Just played the first show on the world tour ... a night we'll remember forever! ... And a very special thanks to our incredible friends Honor Society, Jordin Sparks and Miley Cyrus."