Aston Villa boss Paul Lambert insists fit-again Ron Vlaar is not guaranteed a start in the derby against West Bromwich Albion.
Lambert has been impressed with the way both Ciaran Clark and Jores Okore have performed at centre-half in the Dutchman's absence and the Villa boss is expected to stick with the pair for the derby.
"Ciaran and Jores have been absolutely excellent for us and have struck up a good understanding," said Lambert.
"They're in form and there's a good little partnership developing there.
"In the four games they've played together they've been outstanding, the two of them.
"You earn the right to get into the team and once you're in it, your job is to stay in it.
"Those two lads have been playing really well now."
