On September 4 and 5, the Browns released the following players to get down to the 53-player limit: S Hamza Abdullah, FB Charles Ali, CB Brandon Anderson, QB Richard Bartel, CB Tra Battle, LB Beau Bell, T Branndon Braxton, LB Titus Brown, C Dustin Fry, RB Noah Herron, DT Adam Hoppel, WR Paul Hubbard, CB Corey Ivy, RB Chris Jennings, WR Lance Leggett, G Pat Murray, WR Jordan Norwood, WR David Patten, G Kurt Quarterman, DE Brian Schaefering, G Isaac Sowells, DE Santonio Thomas, and TE Aaron Walker. On September 9, the team elected six players to be captains. RB Jamal Lewis and T Joe Thomas were chosen as offensive captains, LB D'Qwell Jackson and LB Eric Barton as defensive captains, and KR Josh Cribbs and K Phil Dawson as special teams captains.
Question: On September 9th, how many players were chosen as defensive captains?
Answer: 2