The Reds were initially held 2-2 by Brighton, with a save from Gary Bailey late in extra time preventing Gordon Smith from grabbing a win for the unfancied south coast side. But Robson set Ron Atkinson's men on their way in the replay, scoring twice in the first half either side of a goal from Norman Whiteside.
"The replay went well for myself," he told ManUtd.com. "To get the first goal that put us in command was vital. We were 3-0 up at half-time and I can always remember Ron Atkinson saying, 'Don't get carried away'.
"We were so dominant that night. A few of us were looking at each other thinking, 'This game's more or less done and dusted now'. It wasn't over-confidence, we were in such command."
Arnold Muhren's 62nd-minute penalty ensured Sir Matt Busby's 74th birthday was one to remember, as the FA Cup returned to Old Trafford. Robson, on a hat-trick remember, selflessly passed up the opportunity to take the spot-kick, and 30 years later he still has no regrets.
"I was brought down for a penalty and a lot of people think I should have taken it. But if it had been 1-0 to Brighton would I have taken the penalty away from Arnold Muhren, then? I don't think so.
"Arnie never missed a penalty, and it was great for him because I'm sure he was the first Dutch player to score in an FA Cup final, so that was a great moment for him."
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