The Red Devils earned a 1-0 win over the league leaders at Old Trafford, thanks to Robin van Persie's goal midway through the first half.
"It proves when people doubt us, we are more than capable of standing up for ourselves and proving to people that is why we were champions last season," he told PA.
"We weren't champions for nothing. We thoroughly deserved all the points we got last season. This is a step in the right direction going into a busy period.
"People want us to fail because we have won the league so many times. United won the league long before I was here. Everyone hates the best clubs, it is as simple as that. We enjoy that and relish the test we get thrown at us week in, week out."
United return to Premier League action on November 24 when they travel to Cardiff City.