LONDON, Jan 9 (Reuters) - Jose Mourinho has dismissed media reports of unrest within his multi-million pound Chelsea squad and said that Michael Ballack is not alone in needing to improve his performances.British newspapers had claimed that some Chelsea players criticised the contribution of Ballack, who arrived from Bayern Munich at the start of the season in a blaze of publicity but has yet to impose himself on the Premier League. 'I know nothing about this story,' Mourinho told Chelsea TV on Tuesday. 'I have read a few articles like this but I know nothing about it. 'Reports about problems in the dressing room are not correct. Do we want more from him (Ballack) in terms of performance? Not just him, from everybody. 'If the objective is to put some pressure on me then no chance because I pick the team, nobody else does. Press opinions and other players' opinions are not for me.' The Portuguese coach said that Ballack would play in Wednesday's League Cup semi-final first leg against fourth division Wycombe Wanderers. 'I hope it is the first step for him to play in his first English cup final,' Mourinho added.