Speaking to The Birmingham Post, Gold said: "I've got every faith in Steve Bruce, his backroom staff and the players."
"They're steadfast, professional and utterly determined to make it to the final. And the great thing about this team is that they've become very hard to beat. I'd certainly back us over two games against any First Division side.
"Having said all that, I'm still a nervous wreck. What frightens me is that when I look back at the last three play-off semi-finals, there isn't one I thought we could possibly lose.
"When we scored in the first minute of the second leg against Watford at St. Andrew's to make it 1-1 on aggregate three years ago, I was convinced we would go on and win the game. We couldn't score again and we lost it on penalties.
"Two years ago, I thought we were a certainty to beat Barnsley. And what happens? They go and put four goals past us at our place. Game over.
"And don't talk about Preston. Stan Lazaridis almost scores for us at the death at Deepdale, Preston pump the ball up to the other end and they get a second goal with the last kick to make it 2-2 overall.
The rest is more penalties and history - Preston was an absolute nightmare I would never wish to see repeated."
Gold added: "All we can ask for is that we take some kind of lead down to the New Den. I'd settle for 7-0, but we have to be realistic and accept that it's going to be a lot tighter than that. I wouldn't complain if we come out 1-0 up from Sunday's game."