The England international has signed a long-term deal with the north London club after completing a £16m switch to the Gunners from the Red Devils on Monday.
Welbeck, who scored nine goals in 25 Premier League games last season, was facing an increasingly difficult battle for a first-team spot after Radamel Falcao’s arrival.
He’s got his best years to come, I’m convinced of that
However, Arsenal legend Smith reckons a lot of United supporters are disappointed to lose a player that embodies the spirit laid down by former manager Sir Alex Ferguson.
“It’s good news for the player first and foremost and good news for Arsenal,” Smith told Sky Sports News.
“To be fair, I think Arsenal is the only club that Danny wanted to go to and United weren’t all that keen to sell him to a rival, which you can understand. Maybe he stood his ground and they had a change of heart at United.
“I think it’s important that it’s a permanent deal because he’s still only young and he’s got his best years to come, I’m convinced of that.
“Perhaps with Falcao coming in, Manchester United are confident of selling, but I know a lot of Manchester United fans are upset.
“That’s not because they’re particularly sorry to see the player go or the talent that they’re losing, but because he’s a Sir Alex Ferguson player who came through the ranks and encapsulated everything that was good about Manchester United.
“I think they are upset about that.”
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