The England international has linked up with the Vicarage Road club after leaving the Emirates Stadium in June when his contract expired, ensuring he remains in the Premier League.
Welbeck came through the ranks at Man United and made 142 senior appearances for the Red Devils, scoring 42 goals, as well as winning the Premier League title in 2013.
He went on to join Arsenal for £16million the following year, making 126 appearances and scoring 32 goals in all competitions (Transfermarkt).
However, the 28-year-old has not played since last November, when he sustained a serious ankle injury half an hour into a Europa League tie against Sporting Lisbon.
Here is what some fans of Welbeck's former clubs on social media made of his move to the Hornets:
All the best Danny.— P™ | (was @cechque) (@SemperFiArsenal) 7 August 2019
All the very best to you @DannyWelbeck loved you at Arsenal and wanted you so badly to succeed but injuries have made that difficult. You’ll be a bloody good success at Watford, good luck!— Red White Gooner ⚪️ (@RedWhite_Gooner) 7 August 2019
Congrats on the contract Danny! All the best!!!— Spanish Gooner (@elspanishgooner) 7 August 2019
Got a great player there Watford. Always gives 100%, contents threat, great personality. All the best Welbz ❤️— Holdini (@ArsenalVenter) 7 August 2019
Quality player gutted to see him go. Good luck welbz— Ross Assenheim (@RossAssenheim) 7 August 2019
Good luck Danny!— MUFC Core (@MUFC_Core) 7 August 2019
Decent signing good business Watford— (@MUFC_FANCLUB1) 7 August 2019
Brilliant! So happy for you Danny x— Selena (@MancSel) 7 August 2019
All the best Danny boy— MUFC SZN (@UdontKnowMe1238) 7 August 2019
Play well, Ole is tracking you— Lisa (@UnitedSZNLisa) 7 August 2019
Welbeck has also scored 16 goals in 42 appearances on the international stage with England, last appearing for the Three Lions last September, and appeared at Euro 2012, the 2014 FIFA World Cup and the 2018 FIFA World Cup.
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