"We know we are up against it but we're far from out of it and we're going to give it our best shot.
"There were things we troubled them with in the first leg and we've got 90 minutes to go at it. We'll need passion and desire and the lads are determined to battle all the way."
With a place at Wembley up for grabs 13 years after the Millers beat Shrewsbury in the then Auto Windscreens Shield, Robbo also revealed why new boy Simon Thomas could be a key factor.
Thomas joined on loan for an initial month from Crystal Palace last Friday and made his debut with Jamie Clarke in Saturday's 2-0 win over Gillingham.
"Sometimes you want to take the opportunity to have the upper hand or to surprise your opponent, and this was an ideal opportunity to do so," said Robins.
"No one had picked up Drewe Broughton was suspended and we caught Gillingham on the hop because they would have been planning for Drewe.
"We kept people in the dark but surprising the opposition outweighed the desire or the need to tell our supporters that we had a new player.
"It was about getting three points and we did that and, all considered, it was a gamble worth taking. Simon Thomas is raw but there's a fair bit to work with.
"Both he and Jamie Clarke have pace and they will give us extra competition."
MillersMAD understands Clarke is cup-tied for tonight's match having featured in earlier rounds for Accrington, but Thomas should continue in attack.
To follow the game on our messageboard, click on the match thread link on there which will also take you to the head to head stats.