Debuchy was expected to join Nice in the next 48 hours and end a torrid three years at Arsenal but French outlet RMC Sport say the 31-year-old's move has collapsed and the Ligue 1 side are now close to signing Jallet, who has been released by Lyon.
Jallet had been Nice’s top target to play at right-back but Lyon were reluctant to release the 33-year-old who is under contract until June 2018.
But the recent arrival of Kenny Tete from Ajax and Lyon’s decision to finally allow Jallet to leave means he is expected in Nice this evening to join them.
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Nice’s late u-turn will come as major blow to Debuchy who is surplus to requirements at Arsenal.
His career at Arsenal has faltered badly since he suffered back-to-back long term injuries in his first season.
He was then unable to break back into the team as Hector Bellerin quickly established himself in the starting XI in his absence.
Mathieu Debuchy faces having to find another club
Debuchy was left out of Arsenal’s squad which travelled to Australia and China for pre-season training and matches so he could finalise a transfer away from the club.
Lucas Perez, Kieran Gibbs and Carl Jenkinson also stayed behind and are searching for new clubs.
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