Lady Antebellum fans who caught their Los Angeles, Calif. performance at the Staple Center on Tuesday night (March 27) got an added bonus when OneRepublic singer Ryan Tedder joined the country trio on stage, much to the crowd's surprise.

The pop star casually walked onto the stage at the famed arena as the packed house went bonkers with delight -- whether or not they actually knew who they were about to see perform is anyone's guess. Camera flashes and phone recorders were able to capture the unexpected duet between the two music icons, which is now available web-wide thanks to the YouTube video below. Tedder and Lady A's Charles Kelley and Hillary Scott swapped lines back and forth on the hit song 'Good Life,' as the arena echoed with thrilled fans singing the lyrics right back to them.

Following the final notes of the song, piercing screams filled the air as the trio beamed and hugged Tedder, thanking him for making a show to remember on their Own the Night World Tour.

This weekend, the tour -- which also features Darius Rucker and Thompson Square -- will take a brief break so the country stars can head to Vegas for the 2012 ACM Awards. Their road run will resume on April 5 in Moline, Ill., followed by stops in Missouri, Oklahoma and New York. Click here for a complete list of dates where the tour will be rolling through.

Watch Lady Antebellum and Ryan Tedder Perform 'Good Life'