Tom Humphries points out that, though we've a poor record in do-or-die games, that could all change in just one go

Pressure time. Today, Ireland are asked to do what few Irish teams have done before. We have to win with the heat on. Perhaps the biggest achievement of Mick McCarthy's time in charge is that, in Portugal, Holland and various other spots, we have got used to doing that, or something near it anyway.

Irish sides have seldom been good when all the chips are on the table. Back 14 years ago, the charmed existence of Jack Charlton began in earnest when Gary Mackay hit that famous goal for Scotland in Sofia.

We had failed to wrap up qualification ourselves and we would continue to require the comfort of strangers on many subsequent occasions.

Having lost badly in Spain earlier in the group, we needed, not just Alan McLoughlin's goal in Windsor Park, but the right result from Seville that night. In major finals, we couldn't score against the Dutch in Gelsenkirchen in 1988. The game against Egypt in 1990 was a scoreless travesty and against Norway in 1994, knowing that a draw would suffice but a win would be excellent, we mustered our favourite result, another scoreless draw.

After that, we were into the era of the play-off failures. Anfield, Brussels and Bursa. One goal (Houghton in Brussels) from that stretch of football. And in the teething time for the McCarthy team, squeaky, hard-to-take defeats were suffered in Belgrade, Bucharest, Skopje and Zagreb before we learned the knack.

So we play in Yokohama today, knowing that a win is necessary, that if we struggle to score early on the news might paralyse Cameroon and Germany. We need goals and we need at least one before half-time to settle the stomach.

One thinks immediately of Tehran and the parallels are useful. Roy Keane was absent, the opposition was Asian, and if the records are anything to go by, inferior to and less adventurous than today's.

We struggled and in the end fell back into a habit we thought we had left behind - we conceded an injury-time goal and surrendered a long and proud unbeaten record.

Despite their injury problems, the Saudis are in an unusual position today. They can't lose. The worst that can happened already has. They opened with an 8-0 humiliation, the worst thrashing administered at a finals since Yugoslavia saw off Zaire with nine in 1974.

What's more is they kept their manager, Nasser al-Johar, the first native Saudi to lead a team to the World Cup.

They improved considerably by the time they met Cameroon and Nawat al-Temyat, the Asian player of the year a couple of years ago, was especially impressive.

So, today, on an upswing, they play for pride and, as Mick McCarthy points out, that makes them dangerous opponents.

"If I were in their position, I would be saying this is a chance to go home with something. I don't think their mentality will be in any way different.

"They'll be thinking that it would be a feather in their caps to put us out. If we'd been in their position - and thank God we haven't been or the last six days would have been a nightmare - that would be what we would be thinking. We would be saying let's get a little of our pride back."

All of which means that McCarthy faces an unusual tactical challenge today. The evidence is, however, that he has the nous to cope.

In personnel terms, the loss of Keane is still noticeable, despite the herculean efforts of both Holland and Kinsella. Neither has the energy, presence or aggression of Keane, and what we have missed most, apart form the ferocious tackling, is those quick, jabbed five-yard passes into a forward position where the receiving player has scarcely taken the ball than he is presented with the option of returning it to Keane.

Instead, we have been pushing forward slowly, knocking the ball out wide and looking, often without success, for a way to thread the ball behind the opposition defence.

Neither of the goals we have scored have come from that method. Holland latched himself on to a poor clearance against Cameroon and punished it well (This is a traditional source for us, Alan McLoughlin's goal and Ray Houghton's two most famous strikes having come from same.)

For Robbie Keane's goal, we had the luxury so late on of being able to pump a big ball up. "It came from a hoof in the end," said Kinsella of the pass to Niall Quinn. He was right.

Advancing cautiously until he heard Shay Given roaring at him to welly it, Kinsella launched one towards Quinn's head in a manner which would have had old Jack Charlton purring.

Beyond those two moments, both Robbie Keane and Damien Duff have had heroic World Cups without claiming the reward the possession they win merits.

In part, they are too similar as strikers and, while each plays well, they don't appear yet to play well or instinctively with each other.

McCarthy's options today are straightforward. Quinn will get a run at some stage, all that is in question is whether he comes on with sirens flashing or merely to ice the cake.

What will be interesting if McCarthy needs variety before that is whether he gives Clinton Morrison a run. Of the strikers left on the bench, Morrison is the strongest and least predictable.

While Duff's advance billing has seen him draw at least two markers most of the time he prepares to weave with the ball, Morrison's more direct, shoulders-down approach could produce dividends.

Quinn remains the first-choice option to go to, however, and even against Cameroon it was the Sunderland player who was being warmed up when Holland scored.

McCarthy's midfield is a different collective from what he must have imagined when he allowed himself to daydream in vacant moments over the past months. The absence of Keane changed things. Now Jason McAteer's injury alters matters further.

There is a body of opinion that holds that Gary Kelly's leadership qualities will keep him in the side this afternoon as McAteer's replacement. He will play, but the need for him may be elsewhere.

On Saturday, McCarthy was sharp in his defence of Ian Harte, but his irritation at criticisms the full back has suffered did little to disguise the fact that Harte is struggling badly with his confidence.

McCarthy is tremendously loyal to a young player whom he had to blood as an emergency centre half during his first campaign as manager, but he may decide that a key match in the World Cup finals is not the best place to restore Harte's flagging morale.

In that case, Kelly will step in for his nephew, an option he acknowledged existed at yesterday's press conference, and Steven Reid will get the chance to further impress in midfield.

From the time he struck that furious free-kick against Cameroon, having arrived on as a sub in the opening game, McCarthy has known that Reid has shed his tentativeness and arrived as a serious international.

He has such strength, stamina and striking ability that it is easy to see him making the move to the centre of the midfield within the next couple of years.

For now, though, he has outgrown his role as the baby of the panel and become a live option. McCarthy was pleased with the difference he made against Cameroon and Germany and may be tempted to start Reid today with orders to run and shoot as much as possible.

That leaves Kevin Kilbane on the opposite flank as the only other question mark and even that is so faded as to be almost invisible. Kilbane has been in and out of games so far this tournament, but McCarthy rightly regards him as one of the great successes of his reign and the only thing which will keep him off the field today is the ankle strain he suffered at training last Saturday.

Tactically, the bench offers little other options for McCarthy. His centre halves aren't fast, but nothing he has on the sidelines is faster.

The absence of cover for left back has long been a weakness in the team, while the need for an aggressive, driving midfielder is new and might have been met by Colin Healy if circumstances had allowed.

The Saudis like to play a regular 4-4-2 formation, unless they are under severe pressure and then they revert to five at the back. Today, though, they are likely to be adventurous and their best option may be to pack midfield, allowing the runners al-Meshat and al-Temyat to work from there.

An interesting afternoon's work ahead. McCarthy says that the biggest test of his managerial career was the game against Cameroon "for obvious reasons. Well it seemed like it then, but perhaps the next big game is always the biggest test".

Failure today would unravel what looks like being a glorious legacy.