Kwon Alexander made a miraculous comeback from a torn pectoral muscle to play in the playoffs and Super Bowl LIV.

The 49ers linebacker clearly wasn't 100 percent, and it wasn't just due to the pectoral injury he sustained on Oct. 31. Alexander also was playing a biceps injury, something he is having surgically repaired Friday, NFL Media's Ian Rapoport reported Friday.

#49ers LB Kwon Alexander wasn’t just playing in the Super Bowl with a surgically repaired pec. Sources say he was also dealing with a biceps injury that is being surgically repaired today. He’ll have a full recovery for 2020, but amazing to think what he played through this year. — Ian Rapoport (@RapSheet) February 14, 2020

As Rapoport noted, this injury means Alexander's contract now is fully guaranteed for 2020, although there was little doubt he would be back.

Note on Kwon Alexander, whose 2020 salary goes from injury guaranteed to fully guaranteed on April 1. Because of this injury that he’s having repaired today, this confirms he’ll be back on the team in 2020 (if there was any doubt). https://t.co/RF2aJHEKIP — Ian Rapoport (@RapSheet) February 14, 2020

Alexander tore his pectoral muscle against the Arizona Cardinals in Week 9, but somehow rehabbed enough after undergoing surgery to suit up for the 49ers' run to the Super Bowl where they lost to the Kansas City Chiefs,

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The good news is that Alexander is expected to be 100 percent by the time the 49ers open the 2020 season.