West Ham United striker Andy Carroll aggravated his Achilles injury in training earlier this week, and is set to be out for at least two months.
Carroll's injury problems started at the end of last season, when he sustained the injury, and has since been on the road to recovery. During the international break, he's been working on his fitness, only to aggravate his injury further.
Allardyce explained to Sky Sports News: 'Unfortunately for us the specialist said there was a five per cent chance it may break down again and Andy is one of those five per cent unfortunately.
"What we have to do is make sure we treat him in the right manner as quickly as we possibly can again and get it right as quickly as we can.
"It's not frustrating, it is devastating, because we have gone through the process of 16 weeks to go along with specialist reports on how we deal with the rehab when Andy is recovered from this injury."
This will be a big blow to West Ham and their fans, although Allardyce softened the blow with the signing of former Fulham striker Mladen Petric on a free transfer.
With a game against an impressive Southampton side this weekend, and both teams coming off 1-0 losses, the pressure is on for the Hammers to deliver without their star striker.
This is a good opportunity for other forwards at the club to make a mark. Maiga, Vaz Te, and Petric will need to start performing to supply the goals for the team.
Vaz Te in particular will be keen to reignite his West Ham career after falling out of favour recently as his form dipped last year after a long injury lay-off.
You can see how West Ham fare against Southampton on Sunday.
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