Middleton was part of the Highlanders squad which travelled to Cape Town to take on the Stormers in 1999, the only time the Highlanders have been to South Africa for a semifinal in the competition.
That will change this weekend when the side takes on the Sharks in Durban on Sunday morning.
Middleton said the side went into a siege mentality in 1999 and he envisaged the Highlanders doing the same this week.
''It was one heck of an experience. We were up against the odds, having to go over there and play them,'' Middleton said.
''The South Africans did their best to try and intimidate us.
"When we got off the bus going into the ground we had to fight through the crowd and there was plenty of pushing and they were pulling our bags.
''It was a torrid start to the game. But it is a total one-off game. We went into it with an approach that we has absolutely nothing to lose and you can go that extra mile.
"We were real underdogs going over there and no-one expected us to win. Just when you take into consideration the travel and the fatigue factors.''
The Highlanders ended up winning the game 33-18, coming back from being down 11-0 early.
''We had talked about it as a team we had to front up. But we knew we could do it.
"The way things are so professional now the travel is not as much an issue as it used to be. You're flying business class the whole way and getting checked and monitored the entire time.''
Middleton said the advantage for the Highlanders, like the team in 1999, was that the game would be played at sea level.
''If it was up at Loftus it would be a lot different. That would be way harder but at sea level the altitude won't come into it.
''Adrenaline can do a lot in these sort of games. You are 23 guys up against it. You're in a unique position, in a way.
"You get into a siege mentality. They are very close to the ground there in Durban and are very vocal. But you just use that to make you play better.''
Middleton was confident the Highlanders could come away victorious this weekend but they needed to get their set piece worked out.
If they did that then they had a good chance.
