Martina McBride and Train's Pat Monahan will sing "Marry Me" during an onstage wedding at the ACM Awards on Sunday (April 1). Frank Tucci and Christina Davidson will exchange vows during the performance. They were hand-picked by McBride to participate in the segment. Monahan wrote the song for Train's fifth album, Save Me, San Francisco. The duet version is McBride's latest single. McBride is nominated for ACM female vocalist of the year. The ACM Awards will air live from Las Vegas on CBS.