NFL Network Insider Ian Rapoport reported that the San Francisco 49ers were expected to sign Alexander to a four-year, $54 million contract, with $27 million in guarantees.
The team announced the signing on Wednesday night.
It's a huge, eye-popping payday for the 24-year-old linebacker, whose $13.5 million average tops linebackers like Luke Kuechly ($12.36 million).
The big contract comes after Alexander's 2018 campaign ended after just six games following a torn ACL. The former fourth-round pick compiled 380 total tackles and seven sacks over four seasons with the Tampa Bay Buccaneers, making 46 starts.
Alexander is a very good run defender with coverage range. The athletic linebacker should fit perfectly in the Niners' system for defensive coordinator Robert Salah. The rangy linebacker will slide in next to rookie stud Fred Warner and immediately upgrade a 49ers defense that was searching for a replacement after the Reuben Foster experiment failed spectacularly.
San Francisco GM John Lynch paid big for a linebacker coming off an injury, but the Niners have plenty of cap space to toss around this offseason.