GEORGE North will become the youngest player to reach 50 Wales caps tomorrow afternoon – but his boss Warren Gatland believes the giant winger still isn't playing to his full potential.

The 23-year-old Northampton speedster will notch his half-century against Ireland at the Aviva Stadium under five years after his Test debut against South Africa.

North is already up to joint fourth on Wales' try chart with 22 efforts but Gatland believes the 2013 Lion can be even more potent.

"George burst onto the scene and was fantastic but we've got to keep putting pressure on him," said the head coach.

"He'll have 50 caps, which is fantastic, but there is still a lot of improvement in him. He's got the ability to get a lot better than he is at the moment and over the last 12 months he hasn't played as well as we'd have liked, he is aware of that.

"We've been working hard on his game and we put him under a little bit of pressure in the last game (of the Six Nations) against Italy and he scored three tries and got back to some of the form we are looking for in terms of number of touches of the ball and having a real impact.

"Players of that ability have to get their hands on the ball and he went through a couple of campaigns where touches weren't high enough and he made defensive errors.

"What he has achieved at such a young age is exceptional but I don't think we've seen him fulfil his potential and we haven't ruled out in the future that he could be an outstanding centre as well."

North looks likely be shifted to midfield at some stage at the Aviva Stadium, providing Newport Gwent Dragons tyro Hallam Amos with the chance to earn a World Cup spot.

The 20-year-old started at full-back against the Irish in Cardiff earlier this month but should get an outing on the wing, where he was in devastating form for his region last season.

Lock Alun Wyn Jones will captain Wales in the final game before Gatland names his 31-strong squad for the World Cup because Sam Warburton has a minor shoulder injury.

The Wales boss is leaning towards going with 17 forwards and 13 backs rather than a 18/13 split – a decision that would work in the favour of Amos.