The England international was deemed surplus to requirements at Old Trafford following the Red Devils’ loan signing of Radamel Falcao from Monaco on deadline day.
Is it better to look at the instant rather than the future?
The 23-year-old, who was born in Manchester, has penned a long-term deal with the Gunners after they agreed a £16m fee with United.
And former United assistant coach Phelan has expressed his concern at seeing one of the club’s youngsters leave for a rival Premier League team.
“Danny Welbeck has been part of United’s identity and that has been broken. What will happen in the future now, nobody knows but that thread has been broken now,” Phelan told BBC Sport.
“There is always the start of something and maybe this is the start of a new way of doing things at Manchester United and maybe that is the way football is going.
“Is it better to look at the instant rather than the future? It is a difficult one because youth is always the future, we all have to start somewhere and you just hope that product of youth can develop in the Premier League.”
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