Australia v Scotland: Joker Ryan Wilson confident of beating Wallabies in Sydney

Back-row Ryan Wilson is poised to win his 29th Scotland cap against Australia on Saturday

Ryan Wilson says he's got a terrible memory, but some things you just don't forget.

The Rugby World Cup in 2015, for instance. Going along nicely, he was. Started in the opener against Japan, started again in the second game against America, came off the bench against South Africa and came back into the team for the critical pool match against Samoa.

Then came the Australians - and a knock on his door. Vern Cotter wanted to see him. No player wants to get a message like that in such a tumultuous week. No player would fail to read the tea-leaves.

Head coach "Big VC" had nothing for him. That's to say, he couldn't give him the number eight jersey in the quarter-final because David Denton was getting it and he couldn't give him the replacement's number 20 jersey either because, as Denton's understudy in the back row, Josh Strauss was getting it.

So you might say that Wilson doesn't have fond memories of that week. He may have poor recollection, but he remembers what that felt like and he's not likely to forget the devastation of the dressing room either.

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"It wasn't a nice changing room, that," he recalls. "Then we played Australia in the autumn and I split my ankle four minutes in. I rushed off to hospital to get my ankle stitched and didn't watch any of the match. Blood everywhere. Boomf!"

Boomf! You had to be there, in the belly of the Scotland team hotel in Coogee, to understand what he meant. Boomf! is the sound of the blood gushing out of him.

"It was giving it that one, you know," he says, illustrating some kind of explosion in his ankle. "[David] Pocock (the Wallaby back-row), or one of those boys, trod on it and that was it. I played on for two minutes, then I looked down and thought, 'What is going on?!' The cut was really deep, all the way down to the bone. I said, 'Doc, just strap it up'. He said, 'Get off the pitch'.

"A good four minutes I lasted. They had to do a surgical clean. You get your fingers in there and get the mud out. They had to go for it. I watched the game afterwards and what a disappointing end."

Scotland lost to the Wallabies in the 2015 World Cup due to a controversial late penalty

'Screech' turned up without his passport

That was two in a row for Scotland against Australia, two late losses that dominate the landscape of Saturday's Test in Sydney. It's a serious business, but you can't be intense 24 hours a day, you can't live it and breathe it without a break. And Wilson is a pretty good man to switch off.

Humour pours out of him just as surely as the claret did that day in November. He's a fine, robust, belligerent number eight, but he's a funny guy into the bargain. One minute he's talking about the Wallabies and the pain - mental and physical - they have inflicted on his team over the past few years and the next he's telling a story about Screech, a character from the old American TV sitcom Saved By The Bell.

Remember Screech? Odd dude, peculiar hair? Wilson looks at Duncan Taylor and thinks Screech. To be fair, Taylor has described his own haircut as "outrageous", so he probably sees the similarity.

He's got two Premiership winners' medals. He's got two Champions Cup winners' medals. He's got a Saracens' players' player of the year award. There's serious respect for that. Taylor is a hugely admired footballer, but that hair? Respect only goes so far on tours such as this.

"Screech and Spacey are his two nicknames," Wilson explains. "Spacey because he's always spaced out. He tells me his nickname is Dragon at Saracens, which I don't believe. He turned up to the airport without his passport thinking he could get on a flight to Singapore with his driver's licence. There you are, that's Spacey down to a T.

"He sent his cleaner in the house to find his passport. The cleaner couldn't find it so his missus had to leave work and go home and find it for him. I think he got it 45 minutes before we left."

The Scots suffered another agonising defeat by Australia in November 2016

Sleep-walking on tour

There's an unwritten rule within the squad that Wilson must share a room when on tour with John Barclay - or Barclay must share a room with Wilson depending on how you view it. Barclay aired this in his latest BBC Scotland column. He said that, as captain, he's entitled to have a room of his own but that his pal would miss him too much. Wilson would be lost, said his mate.

"I said, 'Don't leave me!' But he wouldn't leave me," laughs the back-row. "I think he enjoys rooming with me too much. I keep him on his toes. He says it's all me, but it's definitely a 50-50 relationship.

"I know he was talking about my sleep-talking and sleep-walking and it's true. Unfamiliar places set me off. I'm quite bad for it. But [Barclay] sleep-farts.

"Just walking round the room picking pillows up and rearranging them. That's what I do. Spacey/Screech/Duncan was telling me he's a bad sleep-walker as well. He built a den in his sleep once and said, 'No! The Romans are coming. No! The Romans are coming!'"

Wilson (centre) shares a room on tour with John Barclay (left)

Wilson has yet to score an international try - something, you suspect, might represent prime mocking material for his team-mates looking to launch some stick. Screech, for example. He's got an answer to him and to everybody else who asks.

"I just do assists," he says. "I do all the dirty work and let all the other boys get the glory. I don't want any of that. I might get one when I feel like it, but I'm the assist king. I like helping people out. [British and Irish Lions full-back] Stuart Hogg wouldn't be where he is without people like me."

'Do we believe we can win? Without doubt'

Parking the wit, he returns to the serious stuff of Saturday's Test, as Gregor Townsend's side bid to repeat the heroics of 2012 - their last visit to Australia, and a 9-6 triumph in a Newcastle downpour.

"Do we believe we can win? Yes, 100%. Without a doubt. There's nobody in this squad that doesn't think we can go out there and do the job.

Ross Ford scored two tries as Scotland beat Italy last weekend in Townsend's first game as head coach

"That might sound arrogant, but you've got to have confidence when you play these big teams on their home patch. We're fifth in the world and there's a reason for that. We're getting better every game. I can see us going out there and winning. It would be a big occasion for us - and a good start for the boss."

With his talking done, he heads for the door, singing the theme tune from Saved By The Bell as he goes. The show was launched in the year Taylor was born and taken off air when he was only four. He'd better get used to it, though. There may be no escape.