The 49ers’ first big free agency move came down just a couple hours after the NFL’s legal tampering period opened Monday. They agreed to terms on a four-year, $54 million deal with $14.25 million fully guaranteed.

Let’s take a look at the full scope of the signing with some key factors and issue a grade.

Fit

Alexander, 24, should slot in as the 49ers’ WILL linebacker once he’s fully recovered from an ACL tear he suffered in Week 7 last season. His athleticism allows him to play coverage, while his instincts and high football IQ allow him to be effective in stopping the run despite his 6-1, 227-pound frame. Missed tackles are a bit of an issue for Alexander, but he’s still just 24-years old with plenty of room for growth before he hits his ceiling.

Contract

A deeper dive into the terms of Alexander’s four-year deal show a very team-friendly contract. The 49ers can exit the deal after this season for just $3 million in dead money. That means his four-year, $54 million contract reads more like a one-year deal. If Alexander isn’t healthy or lacks the athleticism he had before the injury – San Francisco isn’t on the hook long-term. If he is healthy and playing at a high level – they have what looks like a bargain.

Filling a need

San Francisco’s linebacking corps was pretty thin, even with a contract restructure that looks like it will keep Malcolm Smith in the Bay Area for another year. Elijah Lee did a fine job filling in as a starter last year following Reuben Foster’s release, but they needed a higher quality player at that position. Alexander fits that bill when he’s at his best.

Overall grade

While it wasn’t necessarily a splash signing with one of the big-name free agents on the market, Alexander is young and comes to San Francisco on a favorable deal. There’s a ton of upside in the former Buccaneer with relatively little risk.

Grade: B