On May 5, 2014, Alexander was suspended 4 games for violating the NFL's substance abuse policy.[2] Shortly before that suspension was scheduled to end, he was suspended for 10 more games for another violation.[3]
In the second preseason game against the Miami Dolphins, Alexander suffered a torn Achilles tendon.[4] He was waived/injured on August 25, 2015.[5] He cleared waivers and was reverted to the Panthers' injured reserve list. On November 24, 2015, the NFL announced that Alexander would be suspended for a year for his third violation with marijuana.[6]
In the 2015 season, Alexander's Panthers reached Super Bowl 50 on February 7, 2016. The Panthers fell to the Denver Broncos by a score of 24–10.[7]
In 2019, Alexander was selected by the Dallas Renegades in the 2020 XFL Draft.[10] He had his contract terminated when the league suspended operations on April 10, 2020.[11]