Nothing sells a live medley like grabbing a member of the band you're covering for a guest appearance. So Rodrigo y Gabriela fans got a serious treat when Metallica bassist Robert Trujillo joined the acoustic guitar duo for a medley of Metallica songs at the famed Red Rocks Amphitheater in Morrison, Colo. on Aug. 17.

Prior to the performance, the band teased that Trujillo would be joining them for their set with a photo from soundcheck that they posted on their Facebook page. Check out the shot below:

Trujillo took the stage with the duo for an electrifying 15-minute medley of Metallica songs including ‘Orion,’ ‘For Whom the Bell Tolls,’ ‘The Frayed Ends of Sanity’ and ‘Battery.’ See fan-filmed video of the performance posted above.

The bassist has sat in with Rodrigo y Gabriela on multiple occasions over the years, including at the Riviera in Chicago in 2009.

Rodrigo y Gabriela took to Facebook after the show to thank the fans and Trujillo for a memorable night: “Thank you Denver for an amazing night at Red Rocks! And a huge thanks to our friend Robert Trujillo for joining us on stage."

The duo famously covered the Metallica instrumental ‘Orion’ on their 2006 self-titled album. Their latest album, '9 Dead Alive,' was released back in April. The duo plays in Miami Beach, Fla. on Oct. 8.

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