On Sunday night, the Detroit Lions host Rob Gronkowski and the New England Patriots (8:20 p.m., NBC).

According to a published report, Gronkowski almost was traded to the Lions, but the superstar tight end seemed completely uninterested in that idea.

ESPN's Adam Schefter reports that the Lions and Patriots were in serious discussion over Gronkowski, who did not report for most of New England's offseason training programs.

Reports surfaced in June that the two teams were talking about a trade but that talks broke down.

Schefter has shed some light as to why.

According to Schefter, when Gronkowski learned he could be headed to Detroit, he threatened to retire. The 29-year-old tight end, considered by many to be one of the best in NFL history, also did not return calls from Lions GM Bob Quinn and new Lions coach Matt Patricia, both of whom know Gronkowski from their days with the Patriots.

From there, the Pats and Gronkowski talked about him staying with New England, which is what happened, with a reworked contract that added more than $4 million in incentives to his deal.

Gronkowski has one touchdown catch this season and 77 in his nine-year career.