updated 06/15/2011 AT 7:00 AM ET
•originally published 06/15/2011 AT 7:35 AM ET
These stories are “absolutely not true,” Harris’s manager Michael Blakey tells PEOPLE. “This is pure fabrication. There is no relationship, nor has there ever been one. This is a stupid rumor.”
Rumors of a romantic connection between the two first surfaced in March, when Harris and McGraw were reportedly spotted looking cozy at L.A. hotspot Chateau Marmont.
Blakey explains the only interactions Harris, 25, has had with McGraw have been strictly business. “They wrote a song together and that was the extent of their relationship,” he says.