The Red Devils struggled to find their feet in the game and ended up losing to the Baggies to hand the Premier League title to Manchester City.
After a goalless first half at Old Trafford Jay Rodriguez netted the only goal of the game in the 73rd minute to wrap up the three points for the basement club.
And former Manchester United defender Vidic admitted that he was shocked to see the Red Devils slip up and hand the title to their rivals.
Speaking to Sky Sports after the final whistle, Vidic said: “I didn’t expect this. West Brom had a good game today.
“I thought Man United today didn’t move the ball fast enough, they didn’t move without the ball enough.
“That’s what you get when you have teams who come to Old Trafford and defend deep.”
Manchester United will now have to dust themselves down as they prepare for their FA Cup semi-final clash against Tottenham Hotspur next weekend.
The Red Devils have not won the Premier League title since their famous final triumph under Sir Alex Ferguson back in 2013.
Manchester United finished in sixth place in the Premier League table last season and also won both the Europa League and the League Cup.
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