The Wales winger, who was knocked out by Nathan Hughes’ knee immediately after scoring his second try in the Saints’ 52-30 win over Wasps on Friday night, will see a specialist next week to assess his condition.
It is the third head collision to North, just seven weeks after his double knock while on Wales duty against England in the RBS 6 Nations.
He has been into the club today for treatment and will continue to be monitored by the Saints’ experienced medical team throughout the weekend.
Northampton Saints statement on George North
The former Scarlets man also missed Wales’ famous win over South Africa in November as a result of concussion, and he will now faces the prospect of an extended spell on the sidelines before he is cleared to return to action.
Racing Métro outside-half Jonathan Sexton was stood down for 12 weeks last November by a French neurologist after suffering his fourth concussion in 12 months while on international duty.
The Ireland international made his comeback in the second round of the Six Nations, but Mallinder and Wales head coach Warren Gatland could see their deadly finisher ruled out of the remainder of the season and potentially the start of the Rugby World Cup training camp in June.
“After the game North was conscious and in the Saints’ changing room with the rest of the team,” read a club statement.
“He has been into the club today for treatment and will continue to be monitored by the Saints’ experienced medical team throughout the weekend.
“As with everyone in the squad, Northampton Saints places the highest importance on player welfare, and as such North will see a specialist early next week for an assessment.
“Northampton Saints will make further announcements as and when they are available, but no further comment will be made in the meantime.”
While the win extended their lead at the top of the Premiership table to nine points, director of rugby Jim Mallinder was left concerned by the challenge on his star winger by the Wasps number eight, who was red carded by referee Craig Maxwell-Keys after consultation with the TMO.
“I think the opposition have to be very careful once the try has been scored,” Mallinder said after the game.
“It was reckless coming in with the knee and some serious consequences happened because of that.
“George clearly took a bang straight to the head, but he came round and he sat up in the changing room and managed to have a little sing-song.
“He is okay and he was up and walking about, but it’s a knock to his head, which is not good.
“We will look after him and we will make sure that he comes back when he is right. Hopefully, he’ll be okay next weekend.”
Hughes will now miss Wasps’ tricky trip to the Stade Felix Mayol to face reigning European champions Toulon, unless his club can overturn the decision on appeal.
But Wasps director of rugby Dai Young believes his forward did not deserve a red card for the incident as he attempted to chase North down.
“First and foremost, I hope that George is all right,” Young said after the game.
“Nathan has gone looking for him to make sure he is okay.
“He’s not that type of person. Obviously, when you slow anything down in slow-mo, things look a little bit worse than they were.
“But once the crowd gets on a referee’s back, and it was a young referee, there is only one decision that is going to happen. We felt it was a bit harsh.”
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