Stuart Lancaster admits Manu Tuilagi faces a race against time to be fit for England's RBS Six Nations opener, but will give the centre every chance to prove his fitness.
The Leicester man has proved an integral part of Lancaster's plans since he took on the England job and was particularly impressive in December's memorable victory over New Zealand.
However, Tuilagi is struggling to shake off an ankle injury which kept him out of his club's Heineken Cup clash with Toulouse last weekend.
Lancaster is still hopeful the 21-year-old will be fit for England's Six Nations curtain-raiser against Scotland on February 2, but insists his squad has the depth to cope should Tuilagi miss out.
"He's making good progress on daily basis and it's one of those injuries that will go down to the wire," the England chief Sky Sports. "He didn't train today (Friday), but we'll keep working him over the weekend and see what he's like on Sunday.
On when a final decision might be taken, Lancaster added: "It will be Monday or Tuesday really. We'll train on Monday afternoon and twice on Tuesday and by that point we'll have Wednesday off and you need to have nailed down your team.
"But we'll give him as long as possible because he's an important player for us.
"But we've trained with some great options as well, it's fantastic to see Billy Twelvetrees here and Toby's (Flood) running at 12, so we've got some good options."
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