Keown says Chelsea should go with Cahill over Luiz at Benfica
David Luiz is also available for the Champions League quarterfinal.
But Keown told the Daily Mail: "I'd go with Cahill as he and Terry are starting to develop a good partnership. Luiz is a great talent but he is very erratic and it doesn't seem like defending is at the top of his list.
"Also, how can you drop Cahill after his match-saving performance against Tottenham and his goals in the previous two matches?"