The Harlequins full-back was knocked out and taken off in the opening quarter against Italy on 14 February and has been undergoing the graduated return-to-play protocols with a view to making the Ireland game at the Aviva Stadium.
We are of course disappointed to lose him, but Alex is an experienced international and in great form for Saracens.
After waking up with a mild headache this morning, Brown was unable to pass phase three of the multi-stage protocols, so he gives up his jersey after 26 consecutive Test starts.
While Brown continues his comeback with a view to taking the field against Scotland on 14 March, his place in England’s back three will be taken by in-form Saracens full-back Alex Goode, who last lined up for England against Wales in March 2013.
But Red Rose boss Stuart Lancaster has been impressed with the 26-year-old’s recent performances in the Aviva Premiership.
“Mike and our medical staff have been diligent during every step of the graduated return-to-play protocol and they will continue to work to get him back to full health,” Lancaster said.
“The most important thing is Mike’s welfare.
“We are of course disappointed to lose him, but Alex is an experienced international and in great form for Saracens.”
England head to Ireland to take on the only other unbeaten team in the championship after the green machine battled their way to an 18-11 win over France last time out.
Lancaster names his England side to face Ireland on Friday morning.
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