ENGLAND must enter Sunday's RBS 6 Nations title showdown against Ireland without their most ferocious competitor after Mike Brown was ruled out of the Dublin encounter with concussion.
Brown was knocked unconscious during an accidental collision in their 47-17 round two victory over Italy and has run out of time to successfully complete the return to play protocols.
The 2014 player of the Six Nations, who had already suffered one setback in his recovery last week, woke up on yesterday morning with a "mild headache".
Alex Goode will start at full-back at the Aviva Stadium and Brown - an instigator of the recent tunnel stand-off with Wales at the Millennium Stadium - must now switch his attention to proving his fitness to face Scotland on March 14.
"Mike woke up not feeling 100 per cent," backs coach Andy Farrell said.
"The right and proper thing to do was to make the call on him. His health is the main priority here and we need to get him right for the next game. The symptoms aren't too severe. He's fine in himself and is chirpy enough, but it just isn't worth the risk because his health comes first."