West Ham co-chairman David Sullivan has confirmed the club are in the hunt for at least one new striker having lost Andy Carroll to injury. “He wasn’t available until January or February. A mistake was made and we were given the wrong information. We based our decision and our purchase of the player on what the medical department told us. “We’ve changed everything in that department as a result of that. At the same time on his day he is a devastating and fantastic player, we’ve just got to get him back to his best.” Carroll had initially only been ruled out of the club’s two friendlies in New Zealand before the issue was fully understood, with the former Newcastle forward tweeting that he was due to undergo surgery on Friday. “Going under the knife tomorrow morning and absolutely devastated to be missing the start of the season!” he tweeted on Thursday evening. The news will come as a major blow to Allardyce as he looks to improve on the 13th-place Barclays Premier League finish in the last campaign. Meanwhile, the West Ham manager appears to be at odds with the board over the future of Ravel Morrison, with Sullivan stating the owners are keen to keep the former Manchester United youngster at the club. “Sam has said Ravel is not part of his plans but we do – as a board – see him as part of our plans,” Sullivan said. “I think he (Allardyce) said in a press conference, if I read it correctly, he’s not part of his plans for this season. I think he said that in New Zealand but we don’t agree with that. We would like to sit down and give him a longer contract.” Discussions between manager and board will no doubt be required to iron out any difference of opinion regarding Morrison, with Sullivan aware that having the player sat on the bench on a long contract would not be beneficial. “We do like him,” Sullivan added. “We do see him as part of the long-term future of the club but we have to agree it with the manager because there’s no point signing a player if he’s not going to play.” Morrison was left at home as the remainder of the West Ham squad jetted off for their pre-season tour, with the club confirming he underwent successful groin surgery. Having spent time at St George’s Park since his operation, Morrison should be fit and ready to rejoin the first-team squad when they return from the long-haul trip, but it remains to be seen if he will feature in West Ham’s opening Premier League clash against Tottenham. Club-record signing Carroll could miss up to four months after undergoing surgery on an ankle injury, having missed a similar period at the start of last season. Hammers boss Sam Allardyce has already made moves to increase his attacking options with Mauro Zarate signed and Enner Valencia only needing a work permit to complete a move to Upton Park. Press Association But, with Carroll crocked once again, Sullivan insists adding even more firepower to their frontline is now a priority. “We have to bring in another striker and we’re working on it now to buy one, or loan one, or both,” he told talkSPORT. “You can never have enough strikers and really with Andy gone we haven’t got enough. It was desperate last year. We probably made a mistake by putting all our eggs in one basket. “We can’t start the season with the strikeforce we’ve got. I don’t think it’s good enough, there’s not enough height in it and if we get another injury, in terms of quantity, it’s insufficient, so we have to sign at least one more player.” The record fee for Carroll meant there was little left in the coffers for Allardyce, who ended up re-signing Carlton Cole after initially deciding not to offer the England international a new deal. A heel injury proved to be much more serious than West Ham’s medical team had originally diagnosed ahead of Carroll’s move from Liverpool – with the 25-year-old having made just 16 appearances for the club since. “Had we known what we know now we wouldn’t have signed the player,” Sullivan said. “But it’s easy to be wise after the event. We were assured by our physio – who has since left the club – that the player would be available for the start of the season.