Ireland wing Keith Earls says it would be a mixture of relief and pride to bring up his century of caps in the World Cup warm-up against England.

"It would be a massive honour but also just a bit of relief because I was stuck on 98," said the 35-year-old.

"I suppose in the last couple of years I was genuinely thinking every time I stepped on to the field it could be the last time."

The Munster back went more than a year without an international appearance amid fitness problems before being recalled by head coach Andy Farrell for the 33-17 win over Italy earlier this month.

He added: "I'm trying not to think about it but talking to Andy about if it does happen, he's telling me: 'it's not just another cap, you can't have a normal week because it's not a normal week'.

"I'd be extremely proud and privileged to join a unique group."

Earls is set to move alongside Ireland greats Brian O'Driscoll, Ronan O'Gara, Rory Best, Paul O'Connell and John Hayes in reaching three figures, in addition to current team-mates Cian Healy, Johnny Sexton and Conor Murray.

He featured in two of his country's three Tests during last summer's victorious tour of New Zealand but was then sidelined for autumn victories over South Africa, Fiji and Australia and this year's Six Nations Grand Slam success.

Earls believes he has enjoyed the best pre-season of his career as he attempts to secure a spot at his fourth World Cup.

Asked if there were times during the past 12 months when he thought his Ireland days may be over, he replied: "Yeah, especially with the talent coming through and the way some of the lads are playing and my injury history last year.

"But I just kept the head down and I'm grateful. I've a great relationship with Andy and great trust with Andy and we'll always be honest with each other.

"I genuinely have probably had my best pre-season this year as a professional rugby player. We've got everything spot on between all the training, physios, coaches, so it's been really enjoyable.

"I suppose there's that bit of pressure as well because you want to repay them (the coaches) as well but Andy's just big on allowing us to be ourselves and not blowing things up too much or trying anything special.

"It's just be yourself and if you're special, you're special, but it gives you great confidence, especially as an old winger."