The 23-year-old forward has penned a long-term contract with the north London side after the Gunners struck a £16m deal with Manchester United on deadline day.
Welbeck is Arsenal’s fifth signing of the summer after Arsene Wenger snapped up Chilean Alexis Sanchez, defender Mathieu Debuchy, goalkeeper David Ospina and teenager Calum Chambers.
The striker scored nine goals in 25 Premier League appearances last season, leaving Old Trafford having scored 29 goals in 142 games in all competitions since making his debut in 2009.
And Arsenal forward Theo Walcott was quick to welcome his fellow England international to The Emirates.
— Theo Walcott (@theowalcott) September 2, 2014
Welbeck won the Premier League and League Cup during a six-year spell in the United first-team.
An Arsenal statement read: “Everyone at Arsenal welcomes Danny to the club and looks forward to his contribution in an Arsenal shirt this season.”
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