Scotland Under-21 cap Mackay-Steven grew up idolising McFadden as his displays for the national team and Everton in the Barclays Premier League bordered on the audacious.
But 48-time capped talisman McFadden was forced to return to Motherwell in a bid to regain fitness following three years blighted by injury.
His displays so far have been tantalising, with the 30-year-old netting a fine strike following a trademark mazy run against Hibernian last month and then a stunning free-kick against St Mirren last time out for the Steelmen.
United are next up for the Europa League-chasing Fir Park outfit with tomorrow night's Clydesdale Bank Premier League encounter and Mackay-Steven, himself a player who loves to display a range of tricks and turns, is wary of what the old master can conjure.
He told Press Association Sport: "Faddy was a player I always looked up to growing up. He is such a massive player for them and he has done so much in his career. I think he still has much more to offer.
"He's had a few injuries but hopefully they are all behind him now and he can show what a great player he is.
"There's been signs recently that he has still got bundles of ability and that's a worry for us.
"And it's not just him. They have got Henrik Ojamaa and Michael Higdon too. Higdon is always banging in goals, he's got 20-odd this season, and Ojamaa will be there supporting him, so they are dangerous."
- Sports & Recreation