Tottenham goalkeeper Radek Cerny admits his future at the club is uncertain despite replacing Paul Robinson for Wednesday's Carling Cup semi-final clash with rivals Arsenal.The 33-year-old was selected ahead of England goalkeeper Robinson at the Emirates Stadium and produced a solid performance as Spurs earnt a 1-1 draw. However, Cerny does not believe that Tottenham boss Juande Ramos will extend his contract when it expires at the end of the season. 'In my experience, if a club do not extend your contract six months before it expires they are not interested,' Cerny told www.idnes.cz. 'At the end of the season I will probably leave and now every match I play is good for me because I have a chance to show myself earn a place somewhere else. 'I know that the club are looking for a new goalkeeper and everyday new names appear.' Spurs return to Premiership action against Chelsea at Stamford Bridge on Saturday and Cerny added: 'I do not know what will happen. But I will be ready to play. 'I do not feel like I am the number one now. I came as the second keeper and it is very rare that the second keeper goes on to become number one.'