The winger’s extraordinary injury time goal earned United victory at Cliftonville, just minutes after his late equaliser looked to have taken the sixth round tie to extra time.
“You won’t see a better strike this season,” enthused Ferguson.
“I was right behind it, right in line with it and from the minute it left his boot, you knew it was a goal. It was just going like an Exocet into the top corner.
“Peter Cherrie, Tim Allen, Joe Hart - none of them would have saved it.
“The first one took a deflection but if you don’t buy a ticket, you don’t win the lottery.
Cush has had a shot, the wall has tried to charge it and it has come off someone and flicked into the net.
“It gave us a lifeline and got us back into the game and to be honest, at that stage, I would have been happy with extra time.
“Our goalkeeper has kept us in it at 1-0. He has made a great double save and tipped one onto the post and these are defining moments in games.
“Tim certainly did the business and he looked good. We won’t get carried away - it’s only one game but he comes with great recommendations and he’s certainly got the presence to be a good goalkeeper.
“It took a lot of work to get it over the line and he proved his worth.
“To use a phrase he used, he wants to play in European football. Now we’re not Spain, France or Italy but he has played in America and Australia and he wants to come and taste the atmosphere and quickness of the game and play against better players than he has been used to playing against.”
Ferguson said he would have felt aggrieved if the tie had been decided by George McMullan’s penalty - one of a number of disputed decisions made by referee Colin Burns.
“For the penalty, what is Johnny Taylor meant to do? Johnny Taylor is on the ground already and Joe Gormley runs into him.
“For our first penalty appeal, David Cushley is taken out - it could easily have been a red card. The second one, the guy didn’t go and handle the ball, it hit his hand and stopped it from being a tap-in for Matthew Tipton.
“These are decisions which could have cost us very, very dearly. Thankfully it went for us on this occasion but these things even themselves out, our second goal came from a free kick which was never a free kick,” added Ferguson.