Mike Brown will miss England's potential Six Nations Grand Slam decider against Ireland after suffering a setback in his recovery from concussion.

The full-back was unable to progress beyond stage three of the return to play protocol after suffering from headaches.

Brown was knocked out cold when his head clashed with Andrea Masi's shoulder during the early stages of the victory over Italy at Twickenham on February 14, and he was stretchered off before returning to the dugout later in the match.

England head coach Stuart Lancaster said: "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."

Alex Goode is set to come in as Brown's replacement, in what will be his first Test start since the 30-3 defeat to Wales in Cardiff two years ago.

Brown's absence comes after Wales wing George North missed their victory over Scotland having taken two blows to the head in their Six Nations opener against England.

While North has been recalled for Saturday's clash with France, though, England assistant coach Andy Farrell revealed Brown woke up with a mild headache following Tuesday's running session

"This morning Mike woke up not feeling 100%," Farrell said. "The right and proper thing to do was to make the call. His health is the main priority here and we need to get him right for the next game.

"The symptoms aren't too severe whatsoever, just a little headache. He's fine in himself and is chirpy enough, but it just isn't worth the risk because his health comes first."

Farrell admits Brown's experience will be missed in the critical showdown in Dublin, but views Goode as a very capable deputy.

"Mike has been in great form. He's a guy who stands up in pressure situations and performs extremely well. With the young backline we have, he's been a massive help for us," Farrell said.

"But Alex is an experienced guy himself who has been waiting for his chance for some time now. His form for Saracens in the big games against Munster and Clermont and in recent matches has been exceptional.

"Alex is super excited. All you ask for a player who has been waiting in the wings is for them to be ready and we feel he's certainly ready for us."

England fullback Mike Brown was concussed after clashing with Italy's Andrea Masi © Getty Images

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