The 25-year-old has put pen-to-paper to a three-year contract at the Walkers Stadium leaving Hornets boss Malky Mackay disappointed.
Mackay had admitted tabling a bid for the former Scotland international.
The summer transfer window has ended, and all the teams are now set for the season to truly begin.
Zlatan Ibrahimovic claims that he never came close to signing for Arsenal this Summer after he was linked with a
Arsenal legend Thierry Henry has said that Arsenal will now struggle to win the Premier League after they failed to
Arsenal fans have taken to social media to vent their anger at Arsene Wengers failure to secure a single outfield
So, yesterday concluded another English summer transfer window.
Yesterday, Manchester United confirmed the signing of Monaco forward Anthony Martial just hours before the transfer window slammed shut.