NEWCASTLE have been warned to expect an explosive atmosphere this evening.

But, after successfully dodging grenades and mortars in the past, goalkeeper Shay Given has insisted that a hostile Greek crowd will not blow up his side's UEFA Cup hopes.

The Magpies will face a significant test of their mettle when they enter the Georgios Karaiskakis Stadium to face Greek league leaders Olympiacos tonight.

The Athens side have been forced to play their last four domestic home games behind closed doors after a series of disturbances earned their fans a reputation as one of the most volatile sets of supporters in Europe.

Graeme Souness' former club, Liverpool, know all about their hostility. The Reds lost 1-0 at Olympiacos in September and, after receiving scouting reports and videos from the game, Souness has made sure that his side are fully aware of what lies in wait.

But, in goalkeeper Given, Newcastle can boast one player who has encountered circumstances far worse than anything United are likely to face later today.

The 28-year-old, who is Newcastle's all-time record holder for European appearances, was between the sticks when the Republic of Ireland travelled to Iran for a World Cup qualifying play-off game in November 2001.

A staggering 100,000 fans packed into Tehran's National Stadium and, while Ireland's 1-0 defeat was good enough to take them to the World Cup finals following a 2-0 home win in the first leg, it came after Given and his team-mates had been given the roughest of receptions.

"I've been to a few hostile places before so I know exactly what to expect," said Given, who has only conceded two goals in his last four games as Newcastle's defence has suddenly hit a rich vein of form.

"Right at the top of the hostile list would definitely be Iran. I played against them for Ireland in the World Cup play-offs and there were grenades being let off, rockets flying around and all sorts. I don't think it can get any worse that that to be honest.

"It was worst in the warm-up. A grenade was thrown on to the pitch, it went off, and it blew a hole in the ground about a yard in front of me. The dirt flew up and hit me in the face and I'd be lying if I said it wasn't a little bit scary.

"If you can come through that, you can come through anything, and I think the atmosphere will add to the game. Our players will respond to it and get up for things even more."

Andy O'Brien was an unused substitute in Iran but, with Jean-Alain Boumsong ineligible this evening following his European appearances for Rangers this season, the Irish centre-half will play alongside Titus Bramble as Newcastle look to contain an Olympiacos attack likely to include the fit-again Rivaldo.

Boumsong's arrival has co-incided with a definite defensive improvement from the Magpies but, while Given admits that the Frenchman has made a difference, he remains confident in O'Brien's abilities.

"Andy's an Irish international and he knows exactly what he's doing in games like this," said Given. "He's done exceptionally well at international level playing against some of the best attackers in the world.

"He's played against Brazil and most of the top teams in Europe and done extremely well against them. He'll come in for us in Greece and I'm sure he'll do a good job."

O'Brien's return should not be the only change to the side that beat Liverpool at St James' Park on Saturday, as Souness is expected to restore Patrick Kluivert to the starting line-up alongside Alan Shearer.

With the United skipper still adamant that he will retire at the end of the season, tonight's game, and Sunday's FA Cup quarter-final with Tottenham, take on even greater significance.

Shearer is another player well used to playing in front of hostile opposition fans - it is difficult to think of a Premiership ground where he is not barracked every time he touches the ball - and, while the 34-year-old accepts that Olympiacos are one of the best teams left in the UEFA Cup, he is relishing the opportunity to take one of Europe's biggest scalps.

"Any player worth his salt would want to play in this tie," he said. "There is nothing better than playing well and silencing support like they have.

"I think this is the toughest draw we could have got because they are so strong at home. We are here to win though. We are not just here to get an away goal and try to survive. We have won all our away ties and they have won their home ties. Something is going to give."

If Newcastle are to maintain their 100 per cent record in European away games, they will have to inflict Olympiacos' first defeat on home turf since their Georgios Karaiskakis Stadium was completely rebuilt last summer.

The Greek side picked up ten points in the group stage of the Champions League, only to go out following Steven Gerrard's last-gasp goal at Anfield, and have lost just twice in their domestic league all season. But Souness is confident his side have both the attitude and the ability to upset the odds.

Read more about Newcastle United FC here.