AIYEGBENI YAKUBU could retire from international football if it helps to prevent more than a month of his Middlesbrough career being spent on the sidelines.

That is the worst case scenario the striker is bracing himself for as he waits to hear his country's reaction to the news he has opted to pull out of Nigeria's bid for African Nations Cup glory next month.

Having been named in Nigeria's provisional 35-man squad, Yakubu is expected to be named in the official 22-man party for the Egypt tournament, which starts on January 20.

But his refusal to play in Africa's version of the European Championships could lead to sanctions being imposed by FIFA, meaning there is a chance he could be suspended for the duration of the tournament.

That may mean missing as many as nine matches, including both legs of a Carling Cup semi-final should Boro overcome Blackburn tonight.

Boro are keen to do everything by the book and they insist they have done nothing wrong, clearly suggesting Yakubu has made the decision not to represent his country for his own reasons.

"There could be sanctions against the player," said Boro chief executive Keith Lamb. "Yakubu has established himself in the team, ahead of Mark Viduka and Jimmy Floyd Hasselbaink, and feels if he goes to the African Nations Cup he could find it difficult to get back into the team.

"He has explained this to the Nigerian Football Federation. They now have to speak to their coach, Augustine Eguavoen, to see if Yakubu can withdraw.

"We have a proud track record of our players taking part in international football, the fact we let the manager, Steve McClaren, go away with England all the time reflects this."

McClaren is not saying a great deal until he has heard official confirmation that Yakubu will not be heading to Egypt.

"We have got to wait to hear from the Nigerian FA, so there's still a long way to go before we can actually say he's with us for January," said McClaren.

"It's well documented, that he does not have the best of relationships with the present Nigeria coach and I think he's made that known again. It's up to the Nigerian FA to decide whether they withdraw him or not. We are awaiting their decision."

"I have called and told them I am not going to go," said Yakubu, who was annoyed in June this year when he was only used as a one minute substitute in a match with Rwanda.

"Unfortunately, I do not have a good relationship with our national coach. We are not on good terms, so I think it is best that I don't go."

McClaren, who is likely to start the 11-goal striker in tonight's Carling Cup quarter-final against Blackburn, will be a relieved man if his top striker does not miss a large chunk of the domestic campaign.

Since his arrival in a £7.5m deal in the summer, Yakubu has proved himself one of the hottest young goalscoring properties in the English top-flight, grabbing ten goals in 16 league appearances.

There were very few clubs prepared to gamble on the 23-year-old's services when he was, apparently, over-valued at Portsmouth.

McClaren said: "We chased him for over a year and I was surprised there was little competition. He knew we had real belief in him and he wanted to come here to play European football.

"He is more than capable of becoming one of the top strikers in Europe."

When Yakubu and Boro take on Blackburn tonight another low turn out is expected from the club's supporters, with only two sides of the ground open - despite McClaren's men being just three matches away from a trip to the Millennium Stadium.

After Sunday's thrilling 3-3 draw with Tottenham, the Boro boss wants to see his defence show signs of tightening up, having only kept one clean sheet in the last 15 domestic games.

"I can't sleep at night. I'm counting sheep and goals conceded," said McClaren. "It disappoints me after what we did for the first two years, and last season we only conceded one or two goals in the last ten games.

"It has to be a platform. You have to be defensively strong. We need to look at it and to improve on it.

"It is disappointing to think it will be another low crowd. It is not ideal. As a player or a coach, you want a full house but I understand, we have four games at home on the bounce, it is difficult to prioritise. But make no bones about it, this is a very important game for this football club."

Boro youngster Jason Kennedy has been rewarded for his recent first-team breakthrough with a 12 month contract extension.

The 19-year-old's existing deal was due to run until the summer of 2007, but he is now tied to the club until the following year.

* Tickets are available for tonight's tie priced £20 adults, £10 for under 16s and over 65s, from the Riverside ticket office or by calling 0870 421 1986.

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