The West Ham striker has not scored for two months and has only managed nine goals in an injury-ravaged season.
Cole is facing fresh competition for the fourth forward's spot from Bobby Zamora and Darren Bent with Emile Heskey also firmly in the running to go to South Africa this summer.
Mr Reliable: Zola believes Fabio Capello can bring the best out of Carlton Cole
But his manager, Zola, said: 'Capello is excellent at bringing the best out of his players and if he wants to count on Cole, to rely on him, he will be effective.
'It will be down to what he wants from the striker: whether he wants work or scoring goals.
Buoyant Zola and Clarke won't look beyond West Ham survival fightPICTURE SPECIAL: Kevin Mitchell lands knockout blow on Joe Cole WEST HAM UNITED FC