Leicester Tigers lock Geoff Parling believes it will be the "top two inches" that decide the outcome of today's eagerly-awaited Aviva Premiership final.
With two big, hard packs set to smack seven bells out of each other on the hallowed turf, Twickenham will not be a place for the faint-hearted in front of more than 82,000 people.
Parling said the side that can keep their heads, with all sorts of madness going on around them, will lift the trophy.
"We feel we are playing well and had a good win against Harlequins in the semi-final," he said.
"But it's the top two inches that will make the difference today.
"It's about being mentally resilient because these big games are won 'up top'.
"There is a lot of composure needed. You need to able to re-set and go again, stick to your game-plan, adjust to what is happening and concentrate all the time. The approach to the game is key.
"Saints were outstanding in their semi-final. They have a good set-piece but we are a good team too, and we have lots of very good parts to our game.
"Now it's about us getting our parts of the game spot-on.
"We have lost the last two finals, which really hurt us, but there is a good feeling in the camp this week.
"We don't want a relaxed atmosphere but a feeling that we have done a really good job in the semi-final, now let's finish the job."
Leicester will run out for an incredible ninth consecutive final as overwhelming favourites, with plenty of experience over rookies Northampton.
They have also won the last seven fixtures against their local rivals, their last meeting two months ago resulting in a humiliating 36-8 defeat for Saints in front of their own fans.
Tigers will look to get ahead early and remind the Saints players of recent dominance.
But Saints will have taken a huge amount of confidence from their big win against Saracens in the semi-final.
As with any big occasion, the side that gets dominance up front early on will be expected to go on and win the game – and lift the trophy.
The inexperienced Logovi'i Mulipola's battle with Brian Mujati in the front row will be crucial to the outcome of any scrums, while two British & Irish Lions will go head to head at hooker with Dylan Hartley and Tom Youngs.
Julian Salvi's battle with England skipper Tom Wood in the No.7 shirt will determine which side gets quick ball to work with, and the battle of two very spiky scrum-halves in Lee Dickson and Ben Youngs will be fascinating.
Toby Flood's kicking duel with Stephen Myler will see which side keeps the scoreboard ticking over and, in the three-quarters, Tigers will be hoping that Manu Tuilagi can punch holes and unleash their various try-scoring weapons that have, once again, led to Tigers topping the league's try-scoring charts.
The bookies and most pundits will fancy Leicester to land a 10th English title, while most of the neutrals will no doubt be backing the underdogs to a first.
Some 133 years ago, these two sides competed in the first of 227 battles for local bragging rights.
The 228th will be the most important of the lot.
