Davis was signed to a five-year, $35 million contract extension in July. However, just $8 million was guaranteed through a $7 million signing bonus and a $1 million base salary. The Panthers were already without linebacker Jon Beason for the year due to a torn Achilles' tendon.
The Panthers claimed former Baltimore Ravens middle linebacker Jason Phillips off waivers today.
"I would like 2 take the time and thank every1 that has supported me over my career," Davis wrote on his Twitter account. "Unfortunately, I have re torn my acl. Thx 4 da prayers!!"
The Panthers are likely to go with Omar Gaither, but will also consider Jason Williams, Thomas Williams and Jordan Senn.
For more coverage of the Panthers go to profootball.scout.com.
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Thomas Davis tore his ACL for third time
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