The Seahawks selected Sullivan in the seventh round of the 2020 NFL Draft, 251st overall.
Seattle traded back into the draft to nab Sullivan out of LSU, making him the second tight end selected by the club on Day 3 of the draft, joining Colby Parkinson out of Stanford. It was surprising to see Sullivan get drafted before LSU teammate Thaddeus Moss, but Sullivan's profile is intriguing. He's 6-foot-5 and 248 pounds with 35.38-inch arms, and with his 123-inch broad jump and 36.5-inch vertical, Sullivan has a rare catch radius. His production lagged at LSU, as he never recorded more than 363 receiving yards in a season. Sullivan started out as a receiver before moving to tight end, so he's still a project in terms of learning the position. Still, his physical traits make him worthy of a late-round flier.