Sexton was said to be "upset" after failing to reach an agreement with the IRFU, with reports suggesting the out-half was disappointed not to have been offered parity with Heaslip.
But when asked if there was any tension between himself and Sexton, Heaslip replied: "No, not in the slightest.
"He's the ultimate professional. He came in on Sunday night and was good to go... as cranky as ever. The business is done and now he's onto the next challenge."