Johnny Sexton believes the nature of Ireland's 34-10 win against Wales shows how far they've developed in recent seasons under Andy Farrell.

The Six Nations favourites enjoyed a near-perfect start in picking up a bonus-point win away to Wales, their first championship win in the Principality Stadium since 2013.

The groundwork was laid in a dominant first half in which they raced out to a 27-3 lead, and while Wales showed admirable fight in the second half, they never looked like making a comeback, with Josh van der Flier's try 10 minutes from time putting the finishing touches on the performance.

"It was everything we spoke about during the week in terms of our accuracy, in terms of our discipline when they had the ball we were really good," the Ireland captain said of their first 40 minutes.

Having conceded just one penalty in the opening 30 minutes of the game, Ireland found themselves on the wrong side of referee Karl Dickson during the third quarter of the game, consistently putting themselves on the backfoot with penalties, conceding 13 in total during the game.

And while Sexton says they brought the pressure on themselves, he says the way in which they weathered the storm to go on and complete the win shows how they've matured.

"You got a reaction [from Wales] at half-time, but we didn't help ourselves. We gave away five penalties on the bounce when there was no need. All of them, it wasn't an unlucky penalty, they were clear penalties, and it's not good enough. That gave them access, and suddenly you go from a pretty comfortable lead to thinking 'if they score again we're in trouble', and the stadium would have gone mental.

"We held out, and all the messages were: 'we just need to win the next moment'. That's where we've come a long way in the last three years. Test match rugby is difficult, teams will have a purple patch, and the lads did really well to bounce back and get that all important fourth try," he added.

The Ireland captain scored 12 points from the tee in the opening half, before departing on 68 minutes for a HIA following a high tackle by Liam Williams.

The Ireland captain confirmed he passed the head injury assessment, and while he also had to get treatment for a dead leg, he expects to be available for the visit of France next week.

Having missed the last month due to a facial injury, it was only the second game the 37-year-old had played since the win against South Africa in early November.

And having only recently been able to discard a protective mask in training, he admits his lack of gametime had been playing on his mind.

"A little bit, I slipped off one or two tackles trying to go a little bit lower so I went back to tackling higher in the second half.

"It can be in the back of your mind, I tested it during the week, did some contact with Simon Easterby. I felt good, was confident and I got a good whack in the first-half and it was OK. I tested it out as well.

"I don't think I've ever been as nervous as I was before a game. For lots of reasons, but the main one was I'd forgotten what it was like to build up.

"I'd had one game on New Year's Day since South Africa and I got injured in that.

"I trained hard, made some mistakes in training but you want to train well and then hopefully you get a few less on Saturday.

"We came a bit unstuck in third quarter, we just need to look at that and see what we can do better."

Next up for Ireland is a meeting with defending champions France at the Aviva Stadium next Saturday (live on RTÉ2 and RTÉ Player).

The out-half, and head coach Andy Farrell, have played down the game as a potential championship decider given how early it is in the tournament, and Sexton believes they will have to raise their game even further if they're to pick up a first win against the French since 2019.

"It is only a start but at the same time if you come away with a bad result today, the Triple Crown is gone, Grand Slam is gone.

"We're still in the hunt, which is brilliant, it's all down to next week, that's the beauty of this competition, there are no easy games. All five games this year are really tough, and none tougher than next week. The team that hasn't been beaten in a year, we haven't beaten them yet.

"We're up against it, but when we went over to Stade de France last year, it was probably the best atmosphere I've seen, and I'm sure our Irish fans will put on something similar.

"You relish every game you play for Ireland, even if we lost today we'd be relishing it because it's another Test match for Ireland.

"We need to start from zero again, we played unbelievably well for the last 12 days, and it wasn't perfect over the 80, but at half time I was going 'that's pretty good'. We need to keep building, and sort out that third quarter. We can't let that be the first 20 minutes next week, we need to be more consistent through the game."