The Wasps flanker had come off the bench to score in the second half of England’s 41-18 win, but minutes later he had to be carried off on a stretcher after Italy forward Sebastian Negri pulled him out of a ruck.
Willis’ left knee buckled and his cry of pain could be heard at an empty Twickenham. The 24-year-old, who has had issues with his right ankle and knee in the past, is due to undergo scans today and he said this morning he will come back stronger.
“I have loved every second of training and playing in an England shirt and it has been a dream come true to be involved in such a great group of lads and coaches,” Willis tweeted.
“I’m truly gutted with the way it ended on Saturday but these things happen.
“I will give everything I can to my rehab to come back a better and stronger player. Thank you so much for all the messages and support I’ve received it really is appreciated.”