Rory Best has insisted Johnny Sexton will shake off a sore back and be fully fit for Saturday’s NatWest 6 Nations clash with Wales in Dublin.

Fly-half Sexton sat out the opening section of Ireland’s captain’s run training session, to have treatment on general stiffness, but stepped in and completed the session unimpeded.

Ireland will chase a third-straight Six Nations win to keep their 2018 title bid on track at the Aviva Stadium this weekend, with captain Best confident British and Irish Lions playmaker Sexton will be fit to start.

Asked if Sexton was ready for Saturday’s encounter, Best said: “Yeah he’s grand, he’s just getting a bit older, so he needed a bit longer to warm up, but he came into the tail-end of the session.

“He was fine, he finished the session.”

Asked if Sexton would be any doubt to feature fully on Saturday, Best replied: “No, no concerns.”

Ireland will host a Wales side led by Warren Gatland, who will take the national side’s helm for his 100th Test.

Ulster hooker Best worked under Gatland in last summer’s Lions tour to New Zealand, and hailed the Kiwi coach for his ability to move with the times.

Gatland branded England the Six Nations’ best side this week, ahead of facing Ireland – but Best insisted Joe Schmidt’s side do not view that as any snub.

“Look I think he’s entitled to his opinion,” said Best, of Gatland’s view that England are the current best side in the Six Nations.

“He’s coming off the back of having just played England and their record over the last two years speaks for itself.

“But we’ll not really pay any heed to that. We’ll hope that through our performances tomorrow that we can change his mind. And if it doesn’t change his mind tomorrow but we win, we’ll not really be that bothered.

“You can see it in the way Wales have evolved in the last couple of years, there’s no doubt that he’s adaptable.

“To stay for 100 caps at this level is a fantastic feat, and I think we’re very quick to praise players when it happens, so for a coach to be around long enough to do that is a brilliant achievement.

“And hopefully he can get a win in his 101st game to celebrate that.

“That’s ultimately a fantastic achievement, you don’t want to take that away, but obviously we don’t want to give them a win to celebrate it.”

Best will move past former skipper Paul O’Connell’s Ireland Test tally this weekend, when winning his 109th cap for his country.

The 35-year-old front-rower admitted he would draw great pride from surpassing the cap total of one of Ireland’s foremost performers.

“To have played alongside somebody like Paulie and now to have played more times for Ireland than he has, it’s just another one of those little milestones you’ll look back on when you finish up with immense pride,” said Best.

“What he brought to Irish rugby and the amount of times he played is a feat in itself.

“It’s not something I’m overly focusing on at the minute, but I think to go past him is obviously an unbelievable achievement.”