The Blues right-back, arguably the most consistent player of the season so far, is struggling with a thigh injury ahead of the game at Villa Park on Sunday lunchtime.
Melchiot was forced to quit at half time in Blues last home game against Norwich City and despite being passed fit to tackle Arsenal last weekend the Dutch full-back was forced to withdraw 9 minutes from the end of the game at Highbury clearly still troubled with the thigh strain.