The hooker lasted 27 minutes of a bruising warm-up match before injuring a leg when England skipper Owen Farrell fell on him at a ruck.
Lake, 24, painfully limped away off at Twickenham and a scan, due to take place on Tuesday could determine whether Wales coach Warren Gatland picks him in his World Cup squad of 33, when he names it next Monday.
Wales-born back-row forward Taine Plumtree, who Gatland recently recruited from New Zealand, also faces a potential make-or-break scan after being forced off by a shoulder injury.
But there’s brighter news on Taine Basham with Wales backs coach Alex King revealing the flanker or No.8 didn’t suffer a concussion when he copped a shoulder to the head from Farrell, who was sent off for foul play.
Basham, if he continues to pass return to play protocols, could be in contention to face World Cup holders South Africa at Cardiff’s Principality Stadium on Saturday.
British and Irish Lions wing Alex Cuthbert and hard-running centre Johnny Williams may also get a chance to stake claims for places in Gatland’s World Cup party – Wales open their bid for glory against Fiji in Bordeaux on September 10 – by lining up against the Springboks.
“’Cuthy’ is back in training, as is Johnny. It’s about building the depth of the squad. Everyone has been brilliant and it’s great people have had opportunities to be seen in a Test match environment,” said King.
“We will be at full-bore to win the game with South Africa. It’s a really good test for us as they present a good challenge – they have beaten Argentina twice and Australia, and beat England at Twickenham last autumn.”
