George North will make his return and win his 50th cap for Wales in their Rugby World Cup warm-up with Ireland on Saturday, but head coach Warren Gatland fears "one or two more serious knocks" could end his career.

Northampton Saints wing North has been on the sidelines since March when he suffered a concussion that served as his fourth head injury in five months.

North was knocked unconscious during Northampton's match with Wasps back on March 27 after previously sustaining a concussion when playing for Wales versus New Zealand, having suffered two blows to head in the opening game of the Six Nations against England.

The 23-year-old took a break from the game following advice from a neurosurgeon and, although Gatland is satisfied with the steps that have been taken since North's most recent injury, he continues to harbour concern for the former Scarlets man.

Gatland said: "It's not about Wales as a team; it's the individual who is the most important thing. It's his health and making sure that's at the forefront of our decision-making.

"I did express concerns recently that we've got to make sure things are right because if he does pick up one or two more serious knocks that could be the end of his career.

"He's followed all the medical protocols and we were very conservative in the way we approached and made sure that his welfare was paramount.

"Fingers crossed, but when you play this game it's physical. I don't think there's any player at this level who hasn't had a knock of some nature that hasn't jolted them a little bit.

"That's what happens in the game at this level and sometimes some players are more susceptible to it than others."

Wales World Cup campaign sees them take on Australia, England, Fiji and Uruguay in Pool A.