PATRICK LAMBIE, the new Springbok out-half, is a foot smaller than second-row Eben Etzebeth. And six-and-a-half stone lighter. Don't ask me to convert all that into metric for the younger gang -- I failed abacus in the Leaving but, if you do the sums and add up both of their ages, the combined total is well under 50.
Lambie is a gutsy lad. When asked about the bigness issue he said: "All ankles are the same size."
In other words, if you tackle low, the big lads will fall.
He's a dangerous man in space. It's not that he's very small. Young Patrick is 13 stone. For kilos, place 13 bags of Aran Banners on the bathroom scales, of recent origin, and the clock will show you the answer.
The kid kicked well in the Super 15. Patrick is related to the most unorthodox international kicker of them all. 'Broon frae Troon' was his nickname and he was a famous Scots second-row who place-kicked with his big toe.
Gordon Brown played second-row with Willie John McBride for the Lions in the famous series win over South Africa in 1974.
Jonathan Sexton had better be wary. He is bigger than Patrick, though, and is the hardest tackling out-half in world rugby. Jonathan has also learned to control the game but you cannot do that without the ball, and so we come to Eben.
The worst thing from an Irish point of view is he's not just a lighthouse but he can run and pass. Eben jumps higher than a confused springbok in love with an elephant.
The line-out might be a problem. Declan Kidney has gone for toughness and drive. Our locks are easily good enough in the right combination but I would have Devin Toner on for the line-outs. He's around the same height as Eben.
Our line-out will have to keep bobbing and weaving. That's the boxing expression my old pal Tony Heaphy used when he was on the ropes.
Tony was a fine footballer in his day and has seen out many recessions. He's back on top in business now. Tony is still bobbing and weaving against cancer. Good luck old pal. If anyone can beat this, it's you.
There's no one smarter at line-out bobbing than Anthony Foley, Ireland's part-time defence coach. His second-row dad Brendan was only 6ft 1ins. Divide the sum of the hypotenuse by pi squared and add the circumference of a ripe cherry tomato.
It's very annoying. At least the EU left the pint and the furlong as they were.
Brendan was very strong and effectively a fourth back-row. I would have him on my team if he was 5ft 1in.
Donnacha Ryan would be my first pick on any team. And Mike McCarthy is brave, driven and 'Foley-ish'. If they can disrupt the Springboks line-out and win their own throws, we are in with a chance.
The Springboks are the hottest of favourites -- the reason being their injury crisis isn't as bad as ours because there's only a small few hurling and football teams in South Africa.
I unreservedly welcome Richardt Strauss to the Irish team. He has served his time. Richardt will take out citizenship in a couple of years' time.
Imagine when Richardt and his cousin Adriaan were babies back home in South Africa. Did an old Zulu seer look into the cots and say: "Some day these two little boys will compose beautiful waltzes or mark each other in a Test in Lansdowne Road before 50,000 people."
It's our job to predict the tactics. Des Berry from the Evening Herald calculated that the Springbok coach mentioned the word "kick" 27 times at a press conference.
Does this mean the Boks will put the ball in the air and test Simon Zebo, who is playing his first game at full-back for Ireland? It could be a cunning Springbok trick. To get us off our guard. The Springboks then go on to play a running game. Then again, it might just be old fashioned gamesmanship. An unsporting plan to put pressure on Simon.
I hope they do kick at Simon. Our full-back will be fine if he keeps his concentration. The big thing is to get the ball in your hands first and then make the move. Too many players are thinking a step ahead before they catch the ball.
Ireland will punish South Africa if they bomb Zebo. He started out as a Gaelic footballer. A huge advantage. Sure, in rugby the No 15 is seldom forced to catch a Garryowen overhead. Mid-air tackles are against the law. And Zebo could open a safe with a hairclip.
The weather might decide the tactics. Met Eireann make out there's a danger of heavy showers and use the words "fresh and raw" to describe the wind forecast for today. The Norwegian weather forecasters predict a gentle breeze beside a graphic of a crescent moon with no sign of a cloud.
Either way, bring your long johns, thermals and hip flasks. It will be cold.
That might help us. It's mid- summer now in South Africa. Maybe the Boks' hands will be as frozen as Anglo assets and their toes as stiff as welding rods. Who knows?
The one thing we do know is Ireland will have to be at their very best to win this one.