10. David Boston, San Diego Chargers (2003):
Boston was quite the unique case of a free agency bust. The hulking wideout had two 1,000-yard seasons in his first four years with Cardinals. That led the Chargers to sign him to a massive seven-year, $47 million contract that included $12 million guaranteed in 2003. He put up decent enough numbers, with 70 catches for 880 yards and seven TDs in his only year in San Diego.
But it was his mercurial personality and supposedly uninspiring practice habits that prompted San Diego to send him away for the laughable compensation of a sixth-round draft pick. He was suspended for performance-enhancing drugs before the next season, then tore knee ligaments and missed the entire campaign anyhow.
He had four receptions for 80 yards with Miami in 2005 and was never seen on an NFL field again.
