Former England midfielder Tom Cleverley has retired aged 33 because of injuries.
Cleverley, who earned 13 senior caps, most recently played for Watford in the Championship.
He started his career at Manchester United and also played for Leicester, Wigan, Aston Villa and Everton.
Cleverley sustained an Achilles tendon injury at the start of the 2022-23 season before a thigh problem in February.
"No-one could have worked harder than Tom did to make it back from several injuries, which he's tried to do while always providing a positive force around the players," said Hornets chairman and CEO Scott Duxbury.