Merson, who works as one of Sky Sports' top football pundits, admitted he was stunned that United agreed to sell Welbeck after watching the England international score a superb hat-trick against Galatasaray on Wednesday night - and tipped the 23-year-old to outscore the Red Devils' new £350,000-a-week star.
"[Welbeck will] score more goals than Falcao, in my opinion," Merson said. "I was shocked that he was allowed to go. A young English player - very shocked."
Gary Neville also surprised
Merson was not the only person surprised Manchester United boss Louis van Gaal allowed Welbeck to join a direct Premier League rival on the final day of the summer transfer window.
United icon - and Merson's fellow Sky Sports pundit - Gary Neville admitted last month that he failed to see the logic behind the transfer from a Manchester United perspective.
“I have to admit I thought the Danny Welbeck sale was a strange one,” Neville was quoted as saying by the Telegraph. “I can’t work it out.
"Obviously I’m working with him last week and I’m thinking £16 million? There are right-backs and left-backs galore bought for £14 million, £15 million, £16 million. I’m thinking how have they got him for £16 million? I can’t work it out.
"It has helped out a competitor – someone probably vying for those third and fourth places. I am struggling to understand the logic behind the deal in two or three ways.”
United fans pleased Falcao replaced Welbeck?
Plenty of Manchester United fans were of the same opinion, although their disappointment at losing Welbeck was eased when the club announced the loan signing of world-class number nine Falcao.
The Colombia international has contributed two assists in his first three appearances for the Red Devils, but has yet to score his first goal for his new employers.
Falcao will be hoping to open his account for United against Everton on Sunday afternoon.
Welbeck, meanwhile, has now scored four goals in his first five games for Arsenal following his first career hat-trick on Wednesday night.
He will now be expected to fire Arsenal to their first victory over Chelsea since 2011 when the Gunners travel to Stamford Bridge on Sunday.
Falcao v Welbeck
Welbeck scored 29 goals in 142 appearances during his five professional seasons with Manchester United - a record which pales in comparison to Falcao's.
The South American star netted 45 in 105 games for his first club River Plate, before sealing a move to FC Porto, where he scored a remarkable 72 goals in 87 appearances.
He then scored an equally impressive 70 goals in 91 matches for Atletico Madrid, before bagging 13 goals in 22 games last term with AS Monaco.
The two player's respective track records indicate that Falcao should score more goals for Manchester United this season, but will Welbeck prove Merson right?
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