Alexander suffered a season-ending torn ACL in Week 7 against the Browns, leaving him with 45 tackles in six games in 2018. The 24-year-old essentially becomes San Francisco’s replacement for Reuben Foster, the inside linebacker who was released in November after being arrested and charged in a domestic violence incident. Prosecutors dropped the charges against Foster in January. A knee injury that ended Kwon Alexander’s season in Week 7 didn’t affect his market value. The former Buccaneers linebacker has agreed to a four-year, $54 million deal with the 49ers that guarantees him $27 million, multiple outlets reported Monday. NFL trade rumors: DeSean Jackson headed back to Eagles Related News Look at God ! https://t.co/z2cQnF83jv— Kwon Alexander (@kwon) March 11, 2019A fourth-round pick by Tampa Bay in 2015, Alexander has been a starter since Day 1 but has had trouble staying on the field at times. He was suspended for the final four games of his rookie season after violating the NFL’s performance-enhancing substances policy, then missed four weeks early in the 2017 season with a hamstring issue. However, that didn’t keep him from making the Pro Bowl that season as he finished with 97 combined tackles and three interceptions, but another injury kept him from building on that campaign last fall.