Left-back Clapham has been suffering from a throat infection this week whilst midfielder Clemence, although he has returned to first team training, has not fully recovered from the chest injury he sustained during the 2-0 home win against the Villa last month.
Walter Pandiani, however, has shaken-off a slight thigh injury and will be fit for the game at Stamford Bridge.
The home side could field striker Mikael Forssell in their starting line-up.
The Finnish striker, who began the season on loan at St Andrew's before knee surgery forced him return to Stamford Bridge, was a late substitute for Chelsea in their 4-2 Champions League win against Bayern Munich in midweek, his first match action for eight months.
Blues (from): Maik Taylor, Melchiot, Cunningham, Upson, Clapham, Martin Taylor, Pennant, Johnson, Clemence, Anderton, Carter, Lazaridis, Heskey, Pandiani, Nafti, Gray, Tebily, Morrison, Blake, Vaesen.