After defeats at the hands of Manchester City and West Brom in the league thus far, the pressure will be back on in the Sky Live game at Sunderland this weekend, but Vidic is confident they can deliver.
"We have to accept it has not been a great start," said Vidic.
"We have not been getting the performances we would have liked and we also have to be realistic enough to accept we have made some mistakes.
"This team has a lot of potential and we are working really well. Sometimes the results don't come. Sometimes the performances don't come. But I am really positive.
"The most important thing is to defend right. If we defend well, I think we have a really good chance to win trophies.
"The last 10 days have been tough. We lost concentration at certain times, which we shouldn't have allowed.
"We are doing everything we can. We just have to be patient."
Vidic is convinced that United can build on the gritty display in the 1-1 draw in Donetsk in midweek and get back on track at the Stadium of Light.
"I think this is a more important game," he said. "We need to get a few wins in a row.
"The situation is not that bad compared to the teams who you would think will also be competing for the title, or at least the ones who were the favourites.
"We know we have to improve. We know we have to work hard and stick together on the pitch.
"We did that against Shakhtar and hopefully we can do that over the next few weeks because with that kind of mentality we have a good chance to do well."
Don't forget to tune in on Saturday night and watch the Sunderland v Manchester United game on Sky Sports 1 at 17.30