England must stay “united” and focus on next weekend’s “knockout” World Cup game with Australia after losing to Wales, says boss Stuart Lancaster.
The hosts squandered a 10-point lead as Wales won 28-25 at Twickenham, and defeat on Saturday could all but end their hopes of qualifying from Pool A.
“We’ve got a massive game now to build to,” said Lancaster.
“There’s a lot of frustration in the changing room and that frustration has to be turned into a positive mindset.”
England, who led 22-12 early in the second half against Wales, have been criticised for the ill-discipline that allowed Dan Biggar to kick his side back into contention.
Biggar succeeded with all eight of his kicks, seven of which were penalties – including a 50-metre effort that put Wales into the lead in the final minutes.
Lancaster said he was “hugely disappointed” after letting a winning position slip.
“We gave a couple of penalties away which allowed Wales to build belief and momentum. Wales did well to score the points at the end and we didn’t close out the game,” he said.