But, allied to some sloppy play from the hosts, Flood and Robson were instrumental in turning the tide as they got on top of Scott Brown and Stefan Johansen in the middle of the park to send the Dons on their way to a 2-1 fifth-round win.
The experienced pair broke up play and kept the ball moving to the likes of Jonny Hayes and Peter Pawlett just ahead of them. And Robson played a key part in both goals. His 38th-minute corner earned a deserved equaliser when it broke for defender Russell Anderson to volley acrobatically into the roof of the net, and the former Scotland midfielder played Pawlett through four minutes into the second half to fire in off the post for the winner after charging down Johansen's attempted clearance.
McInnes said of his midfield pair: "Both players want to get after the game. Both players are the type who just want to compete and get after them.
"But you have got to pick and choose your fights out there. The two of them gave us a platform to turn the ball over. They stayed in their slots when they needed to, when they came out there and there was a ball to be won an put them under pressure, they did that.
"But both of them used the ball extremely well and brought an intelligence to the game, and I thought that was important.
"Barry has played a really disciplined performance, but we still said to him, 'you will get chances to affect it, use your quality'.
"The wee reverse pass to Peter was terrific. He doesn't snatch at it, he's got the wherewithal to slip him in and Peter finishes it brilliantly."
Robson told Red TV: "The manager spoke to me before the game and told me exactly what he wanted. Thankfully I managed to do that, play disciplined and move the ball and try to feed the players in front of me. The manager studies everything and got his tactics spot on."