With lipstick on his face, Thomas Rhett accepted the ACM Award for Single of the Year on Sunday night. "Die a Happy Man" may have been a surprise win, despite its multi-week run at No. 1.

The ballad from Rhett's Tangled Up album topped five other songs, including "Buy Me a Boat" by Chris Janson and "Girl Crush" by Little Big Town. It was a platinum-selling hit that rapper Nelly even covered for pop radio, and it's the most personal song the 26-year-old has ever written.

"Die a Happy Man" was written as a love song for Rhett's wife Lauren. She had been begging for a true love song, and he delivered with help from Nashville outsiders Sean Douglas and Joe Spargur. Once on stage, Rhett thanked his young bride first, and then his label and management team and God.

The award was Rhett's first in three nominations at the 2016 ACM Awards. He lost to Chris Stapleton in both the New Male Vocalist and Album of the Year categories. It's his first ever ACM Award. He'll perform the song later during the show.

See How Thomas Rhett's Wife Inspired "Die a Happy Man"

Look! The Hottest Looks From the ACM Red Carpet