As a player, Gattuso did not sleep before big games. It's similar as a manager but he now has the aid of sleeping pills from his doctor.

Otherwise, he says, "at 4.30 or 5am I wake up and I'm wide-eyed like a bat".

Gattuso is carrying the weight of a nation on his shoulders. It's a big responsibility.

The former AC Milan midfielder stepped into the role to replace Luciano Spalletti in June, and has won five of his six matches.

"I've been coaching for a number of years now, but certainly this game is the most important fixture of my coaching career so far," said Gattuso.

"I'm prepared and, believe me, I'm not thinking about things going badly, I'm thinking positively.

"I want to think big, and we certainly will compete and we'll see how things come out."

He has admiration from O'Neill, who in 2012 was tasked with a similar job of trying to lift a Northern Ireland side at a low point.

Four years later they qualified for the Euros.

"The pressure of managing Italy is a lot different from the pressure of managing Northern Ireland," O'Neill said.

"I have admiration for him coming in and taking the job at the time that he did, after the previous manager leaving after two games and then having to try to reverse a poor result in the first game for Italy away in Norway.

"I have great admiration for what he did as a player and, obviously, the job he's done as a coach as well."

Throughout Gattuso's press conference, Gianluigi Buffon sat quietly at the side of the room and watched his World Cup-winning team-mate speak.

Now Italy's technical director, Buffon played a key role in appointing Gattuso to replace Spalletti in June, and he is also fully aware of the pressure that is on the shoulders of the Italians.

In contrast, by the time O'Neill arrived for his press conference, a storm had rolled into Bergamo and the blistering sunshine, which the thousands of travelling fans had been lapping up, was replaced by lightning and thunder, which was so loud it could be heard in the media room when O'Neill was speaking.

If the game on Thursday is as dramatic as the changing weather, then we will all be in for a treat.

O'Neill says his young squad will play without fear.

"I have a lot of belief in this group of players and it will be a young team that will take the field.

"I think the benefits you get with youth is a lack of fear. We have everything to gain in the game, there's no doubt about that.

"Over the past two years they have really grown and played a lot of international football.

"It will be a huge test for us, but it's a test that I believe we're ready to take."

There is a lot on the line for Italy, and emotion is set to play a big role in Bergamo.

Gazzetta dello Sport, one of Italy's biggest newspapers, ran an interview with 2006 World Cup-winning manager Marcello Lippi, who said Gattuso reminded him of himself as a manager.

That, for Gattuso, "brought a tear to my eye".

Northern Ireland's fight and desire was a constant theme in Gattuso's press conference, and it is clear he wants his side to match that on Thursday.

As he said, "we are the masters of our own fate".

"First and foremost, it's up to us.

"We have to go out there on the pitch and if we show in the stadium that we're on the money and we don't have any fear, then we can't ask anything of anyone.

"We know very well what we need to do. We need to make sure that we're ready for this game, both physically and mentally."

For O'Neill, he knows his squad have the belief that can pull off something special.

"I think we have to realise that we've done incredibly well to be at this position. There's a lot of bigger nations than us that are not at this point in the competition.

"Being the smaller nation and with the expectation that sits with the home nation, we come into the game a little bit looser, and with a little bit more freedom in ourselves.

"I'm incredibly proud of the players. They know what's at stake."