Ashley Greene & Stephen Amell: iHeartRadio Music Festival Presenters!

Ashley Greene dons a sexy black dress while attending the 2013 iHeartRadio Music Festival at the MGM Grand Garden Arena on Friday (September 20) in Las Vegas.

The 26-year-old actress was joined on the red carpet by Stephen Amell and athlete Shaun White.

PHOTOS: Check out the latest pics of Ashley Greene

Later in the night, Ashley and Stephen introduced Matthew Bellamy‘s band Muse, who took the stage after Keith Urban.

“Just did a huge photo line with my fly down. Not on purpose. Dead sober. I’m 32 years old,” Stephen tweeted at the music festival.

FYI: Ashley is wearing Monika Chiang shoes.

10+ pictures inside of Ashley Greene and Stephen Amell attending the iHeartRadio Music Festival…