The 30-year-old forward re-signed for the club on Friday, shortly before the Steelmen were drawn against Russian outfit Kuban Krasnodar in the third qualifying round of the Europa League.
Motherwell exited the qualifying stages for both the Champions League and the Europa League at the first hurdle last year, at the hands of Panathinaikos and Levante respectively.
But McFadden is hopeful they can progress further this time around with a bit more self-belief.
He said: "It's going to be tough. Regardless of who we got in the draw it was going to be a tough game.
"But I think we've got to believe we can win the game.
"We need to go there and play to the best of our ability and hope it's good enough.
"They are in Europe so they must have had some success last year and they will be strong.
"But we must believe we can win. We are not here for fun; it's not a day out.
"The manager has brought in some really good players and we have to have confidence that we can win the game."