Taylor Swift reportedly wrote Calvin Harris' recent hit song

The creative portion of Calvin Harris' mind must have a blank space.

Taylor Swift could actually be the mastermind behind her ex's recent smash hit "This is What You Came For," according to TMZ.

Swift, 26, wrote the song, played it on piano and then recorded it on her phone before sending it to Harris, 32, the gossip site reports.

The site also claims that the "Blank Space" singer used a fake name on the credits of the dance jam, Nils Sjoberg, in order to keep the publishing rights.

On the same day the song debuted, Harris said in an interview with Ryan Seacrest that he and his talented musician girlfriend, Swift, never even discussed if they would make music together.

"You know we haven't even spoken about it," Harris said on the radio show. "I can't see it happening though."

A source told TMZ that after the interview, the Grammy-winning songstress was hurt by Harris' remarks and the relationship headed in a downward spiral from there.