Alex Marvez of Fox Sports reported Wednesday that Alexander has required "multiple" surgeries on his right knee because of an infection after undergoing a second reconstruction of his ACL in January, according to a source.
The latest setback could cost Alexander the entire 2014 season.
Marvez reported that Alexander has received intensive antibiotic treatment to go with the multiple surgical procedures, according to the source.
Alexander tore his ACL during training camp last August, then needed a "revision" ACL surgery five months later. Alexander, 25, has undergone five previous surgeries on his left knee.
Alexander has shown himself to be resilient in the past, and emerged as Philip Rivers' most productive target during a rare healthy stretch late in the 2012 season.
But the latest setback is an ominous one. It's likely the Chargers and other teams will be scared off by Alexander's continued health struggles.