Amid the offseason uncertainty surrounding Brandon Aiyuk, the 49ers checked in on Justin Jefferson's availability before this year's NFL draft, but the Vikings had zero interest in trading the star wide receiver and immediately rebuffed San Francisco's inquiries, league sources told ESPN.

The 49ers were not the only team to check in on Jefferson. The Jets and Colts also had some level of interest, but the Vikings never considered moving the three-time Pro Bowler and talks never went anywhere, according to sources.

Those inquiries came before the Vikings signed Jefferson to a record deal in June, making him the highest-paid wide receiver in NFL history. Inquiring teams thought they might be able to tempt Minnesota into attractive trade packages, but the Vikings only were interested in re-signing one of the league's top players.

San Francisco faces Jefferson and the Vikings on Sunday, and 49ers head coach Kyle Shanahan knows what type of receiver his defense will be up against.

"There's not an angle he can't really run at -- at full speed and drop his weight," Shanahan told reporters. "He's also fearless in how he plays. His hands are as good as anyone. From what I've heard from people who have been with him, they say he's one of the smartest players that people have been with. He's the full package."

The Vikings signed Jefferson in June to a four-year, $140 million extension that includes $110 million guaranteed, sources told ESPN. Less than three months later, the Niners ended their contract stalemate with Aiyuk by signing him to a four-year, $120 million extension that includes $76 million guaranteed.

Vikings general manager Kwesi Adofo-Mensah said at the NFL scouting combine in February that a Jefferson trade never crossed his mind -- even if it would help him trade up for a quarterback in the draft.

The 2022 Offensive Player of the Year, Jefferson entered this season averaging 98.3 receiving yards per game -- the most in NFL history for any career span.

Jefferson, 25, set an NFL record for most receiving yards in the first three seasons of a career (4,825) and then eclipsed 1,000 yards last season despite missing seven games -- and parts of two others -- because of injuries. His 1,074 yards in 2023 were the most ever by an NFL player who played 10 or fewer games in a season.