In an open letter to fans, posted on the club's official website, Sullivan - who recently completed a takeover at Upton Park along with David Gold - unveiled his anger at the team's 3-1 home defeat to Wolves on Tuesday night, slamming the performance as "shambolic" and "pathetic". England centre-back Matthew Upson immediately dismissed the comments as "irrelevant" and gave his support to Zola, whose position has come under increasing pressure with the Irons hovering just above the relegation zone. Zola was less than impressed by the latest turn of events in what has been a rollercoaster season at the Boleyn Ground, but insists his full attention is now on beating Stoke on Saturday. "The owner is entitled to have his opinion and express it, because he is the owner," said the former Chelsea forward, appointed in September last year after Alan Curbishley's departure. "However, when you use those words, you have to be very careful how you use them because sometimes they can be painful and cause more damage than you can imagine, and that could be the case. "How will the players be feeling?" Zola continued: "I was very disappointed and he will know that, although I have not spoken to him directly. "It is not pleasant. But I am not going to retaliate or answer back. "I will keep my focus on my job, I have a responsibility and will turn it into a positive thing for me and players. "I will keep my head down and focus on the job. Now we just have to focus on playing, and stop talking." Chants of "you're not fit to wear the shirt" also rang out around Upton Park during the crushing 3-1 defeat by a side also looking to pull clear of danger. Afterwards striker Carlton Cole was involved in an altercation with one such disgruntled supporter following what was a fifth straight defeat and one which left the Irons just three points above the drop zone. Both Gold and Sullivan have called for the fans to get behind the team, a sentiment echoed by the Irons manager. Zola said: "I can understand the frustration of the fans, because the team is not doing what people expected. "It is just about faith. "When things are not going well, but West Ham is our team and we have to be supportive for 90 minutes. "After that, we can express an opinion if we have not done a good job. "But when the players are on the pitch, we all have to be supportive and the players need to feel we are behind them." Zola added: "We know that we have to produce a fantastic performance against Stoke. "The good thing is that I do not need to motivate the players with a team talk tomorrow, because they have already had one." Zola firmly believes West Ham have the quality in their squad to beat the drop. He said: "We are a good team, but going through a difficult moment. "We need to make sure we show everyone we are a good team and are going to try to show that tomorrow. "I am not happy with the situation, the position we are in, but everybody is trying very hard. "We care and are trying to find focus in a difficult position to do a good job for the club." Zola added: "I do not think the players are not passionate, against Wolves they were trying to sort the situation out more like an individual. "That is my mistake - we have worked on that, and hopefully they will fight like a team. "We have to win as a team, which is the most important thing. "Everybody wants to give 200 per cent, but that has to be given in the right way." For the moment, Sullivan and Gold look set to give the Italian a chance to turn things around, despite the likes of former England manager Glenn Hoddle and Mark Hughes, sacked by Manchester City, being linked with the job. Zola certainly has no intention of quitting. "While I can see that I can so something good for this club, I am not going to walk away," the Italian declared. "A lot has been happening, but if I can be helpful, then why shouldn't I be here?"
