Warren Gatland faces an anxious wait to discover the extent of a knee injury suffered by Gareth Anscombe in Wales' 33-19 Rugby World Cup warm-up defeat to England on Sunday.

The fly-half was helped off in the first half at Twickenham with a damaged left knee, after England lost Tom Curry to what appeared to be an arm injury on the eve of Eddie Jones' World Cup squad announcement.

Anscombe watched on with a pair of crutches as rusty Wales incurred a loss which prevented them from replacing New Zealand at the top of the rankings.

Wales head coach Gatland said it was too early to judge for how long Anscombe might be out of action, less than six weeks before the World Cup starts in Japan.

"I've spoken to the physios. He's [Anscombe] got to get a scan. If it's a strain, he'll be out for a few weeks. We'll find out. I wouldn't want to be naming my team on Monday," said New Zealander Gatland.

Gatland was less concerned by an injury sustained by flanker Justin Tipuric.

"He just slightly rolled his ankle. I don't think it's an issue," the Wales head coach added.

Gatland also revealed Tomos Williams (shoulder) will undergo a scan on Monday after missing the clash in London, while Adam Beard has a strained wrist.

The Six Nations champions failed to match the intensity of a fired-up, experimental England side, but Gatland says they will be much improved when they attempt to gain revenge in Cardiff next weekend.

"We went into the Six Nations match with a strategy but today we tried to play differently to work things out. England did what they do," said Gatland.

"We've got a couple of things to work on. We need to be more accurate in attack. We addressed a few things at half-time and they're pretty fixable things. We'll work on them this week and we'll be a lot better for it."