Giovanni Trapattoni is confident Caleb Folan will be fit to replace Kevin Doyle in the World Cup qualifier against Bulgaria, but the Hull City striker did not join up with the Republic of Ireland squad in London today because of a knee injury.

The calf injury sustained by Doyle in the first leg of the Championship play-off semi-final against Burnley always looked likely to rule him out of Friday’s friendly with Nigeria at Craven Cottage and the June 6th game in Sofia, but the manager must now wait on news from Folan, with the striker set to undergo a scan back at Hull.

Though he insists Folan will join up with the squad on Monday, Trapattoni today pointed to the fact he already has a player of similar stature and style in the squad, in the shape of uncapped Coventry striker Leon Best.

“Caleb will be okay after the rest, and on Monday he will be with us,” Trapattoni said. “I also have Leon Best. He is a different player but he is a similar build and can play that way.”

Nevertheless, it is will disappoint the Italian that he will not have a chance to partner Robbie Keane with Folan ahead of the crucial game against Bulgaria.

Best and Shane Long both look sure to feature against Nigeria now, in a side that is likely to be severely lacking in experience.

Manchester City goalkeeper Shay Given has a hip injury but would have been rested anyway to give Keiren Westwood a chance, while Preston pair Sean St Ledger and Eddie Nolan are also set for debuts.

Another debutant is likely to be Stoke City’s Liam Lawrence, could be in Las Vegas celebrating Premier League survival right now, but he was happy to swap his holiday for a chance at getting Ireland closer to next year’s World Cup.

“I was supposed to be in Vegas with the Stoke boys for a celebration but that got cancelled sharply and I unpacked the shorts and flip-flops,” Lawrence said. “I’d give that up any day to play this week.”

The 27-year-old midfielder is hoping to make an impression.

“It’s good to be back in the squad and hopefully I’ll get my chance. I didn’t think it was going to come but I’ve been playing every week and doing well.

“It’s given me a chance and hopefully I’ll take it. The bar is raised again and it is up for me to step up.

“I was speaking to Glenn Whelan when I wasn’t getting called up and he was telling the future is looking bright. There is a great chance to qualify and this group of players is good enough. The World Cup is definitely achievable.

“Friday is a big chance for me to make my mark and hopefully I’ll get a look in - I’ve been waiting 27 years for this.”

The senior players Trapattoni selects are likely to be given a half at most against Nigeria to keep them fresh for Bulgaria, a match that will give them a huge stride towards at least a play-off place if they win.

Damien Duff is among the players in that category. Duff scored the own goal that confirmed Newcastle’s relegation at the weekend, and Trapattoni hopes international duty can provide a welcome distraction.

“I thought yesterday that he was a bit sad,” said the boss. “Sure, he is not happy but football is like this. I told him he has to score in the next game.”