We face United in a 5.30pm kick-off on a run of six matches unbeaten in all competitions.
“We are in good form and I think good things can happen,” said Jan, who has been outstanding this season and scored his first goal for us in Wednesday’s 3-0 win at Carlisle in the Capital One Cup.
“We can be positive. We have a good team, we’re in a good flow and I think we don’t have to hide, we have to be positive.”
Belgian international Jan has been counting down to Saturday’s big clash.
“It’s one of the reasons I came to the Premier League, to play in big games against the best players in the world. That’s going to happen on Saturday and I’m looking forward to it.”