Toby Flood faces a taxing fitness test today as he bids to prove his readiness to face Scotland on Saturday.
The fly-half, who had his best game in an England shirt against France last weekend before being forced off at half time with a damaged shoulder.
Gloucester's Olly Barkley has been drafted in as standby but Flood has recovered well since Sunday evening and is confident he will be fit for the Calcutta Cup showdown.
Flood said: "Thankfully it is not as bad as that injury from the summer because that kept me out for four to five weeks. That is what I was worried about at the beginning but it has settled down quite well.
"I am really surprised how well it has come on. I thought there was no chance and that I would be out for a couple of weeks. Now I am confident I will be involved at the weekend.
"I have a fitness test today. They have kept it under wraps to I can't go out there and practise it - but I think it will be a bit of running, moving, hitting backs, falling on it, clap press-ups, that kind of thing."
It is likely to be tomorrow before England's medical team make a final decision on the fitness of Flood and flanker Joe Worsley, who suffered a cut hand in the same game.
Flood was injured in the build-up to England's fourth try that was eventually scored by Worsley and remarkably put them 29-0 ahead at the interval.
"I didn't want to come off," said Flood.
"It was massively frustrating, especially the way things were going and how enjoyable the game was. It felt like there was no real pressure and it was us out there just to express ourselves.
"That has happened a few times for Leicester this season but it doesn't happen much in international rugby. It was a good thing to be a part of."