NEWCASTLE United's Gary Speed fears his season could over after suffering his latest injury setback.

It was hoped that the influential midfielder would be in contention for Saturday's home game against Manchester United after missing the defeat at Everton with a recurrence of his groin injury.

But Speed has revealed that if there is no improvement he could be forced into undergoing surgery for the second time in four months - ruling him out of the last six games of the season.

"It's a bit of a nightmare really because if I have another operation now it means I will be out for the rest of the season," said the 33-year-old Welsh skipper.

"I'm going to give it another couple of weeks to see if my hernia gets better. I'm hoping to feature in the last few games of the season - all I can do is wait and see."

Speed was on international duty for Wales against Azerbaijan in the Euro 2004 qualifier at the Millennium Stadium last month when the groin trouble he first suffered in the game against Spurs back in December returned.

Earlier this season he underwent a hernia operation, and a subsequent six week lay-off saw Speed back to his best as Newcastle stayed on the tails of the top two in the Premiership.

But if the veteran midfielder is now forced to go under the knife again, then Sir Bobby Robson will be without two of his best midfielders for the remainder of the season - Hugo Viana is also out after dislocating his shoulder for the second time this season in Portugal Under-21s' win over England.

Meanwhile, Speed is still disappointed at the two refereeing blunders which he believes may have cost Newcastle their chance of the title this season.

Speed watched from home as Newcastle were defeated at Goodison Park on Sunday against his boyhood club Everton, with Thomas Gravesen's challenge on Olivier Bernard dominating the post match debate.

Speed said on his ICONS.com website: "I was gutted for the lads on Sunday, but there is not much anyone can do against such appalling refereeing.

"I am still fuming that nothing was given against Thomas Gravesen for his tackle on Olivier Bernard.

"I just can't understand what the referee was thinking of. That's the second time we've been fouled in midfield when the referee has been right on top of it.

"Nothing has been given and the opposing team has gone on to score the winning goal.

"It was a similar scenario against Middlesbrough a couple of weeks back when we lost 1-0.

"Against Everton you could see the referee look back a couple of times after it happened so he'd obviously seen the foul.

"I just can't understand why he hasn't given it.

"That's at the very least two points the referees have cost us and without those points now we're certainly out of the title race."

The club have decided not to make any official complaint about Scunthorpe referee Neale Barry's handling of Sunday's game at Goodison Park.

* Newcastle United will make no decision yet on whether their planned trip to the Far East in the summer goes ahead.

Fears of the deadly severe acute respiratory syndrome, SARS, virus have already seen Everton cancel their end of season tour to China, and United are due to play in the Malaysian capital of Kuala Lumpur at the end of July along with fellow Premiership outfits Chelsea and Birmingham City.

Asia is currently struggling to combat the effects of the virus which has killed over 100 people and which has now spread to Canada and Europe.

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