England manager has Martin Johnson breathed a sigh of relief after Courtney Lawes was cleared of a serious neck injury.
The Northampton lock had given Johnson a scare less than six weeks before the World Cup when he was stretchered from the field with his neck in a brace during a behind-closed-doors trial match. Lawes was given oxygen and transferred by ambulance to Charing Cross Hospital, where he underwent precautionary scans on suspected soft tissue damage.
The 22-year-old was subsequently discharged and will undergo further assessment by the England medical team when the squad gather back at Pennyhill Park on Sunday evening.
Saracens wing David Strettle was also carried off, having suffered an apparent leg injury in the first period of a full-contact match at The Stoop, played in two 20-minutes halves.
Johnson mixed the teams up - there was no distinct A and B team - but there was one notable absentee in Mike Tindall, who is getting married on Saturday.
Leicester number eight Thomas Waldrom is carrying a calf problem and also played no part but Manu Tuilagi showed glimpses of his growing promise at outside centre.
Jonny Wilkinson also made an impact after coming on, helping create a try for Mark Cueto early in the second period as the team in white won 11-10. Tuilagi and Tom Croft scored for the black team.
"It was a good end to the week and the boys enjoyed having a run out in a different environment," said Johnson.
"Inevitably it was competitive and you wouldn't have it any other way. But to be honest the whole training camp has had that edge that you want from a group of players vying for 30 spots."
Johnson is understood to be cutting six players from his 45-man squad this weekend ahead of England's first World Cup warm-up match, against Wales at Twickenham on August 6. England then play Wales away before Johnson has to finalise his 30-man World Cup squad on August 22.