For Peter O'Mahony, emotions had been high all week leading up to arguably the biggest night of his Ireland career.

As a passionate Irishman, losing in English rugby's great fortress is always painful, but with O'Mahony's yellow card weakening Ireland's resolve at a crucial time, the early part of this week would have been torturous for the Munster veteran.

But having come through what would have been a particularly stinging review for himself, O'Mahony was central to driving Ireland over the line against Scotland on Saturday, delivering the team's second consecutive Six Nations title.

It is O'Mahony's fifth championship, and first as captain. But will it be his last? As he soaked up the adulation with his family and team-mates amid a party atmosphere in Aviva Stadium, it was hard not to wonder if it was his swansong.

Having worn down Scotland on a nerve-shredding evening in Dublin, which reminded one of last year's Grand Slam decider against England, the Ireland players could finally breathe at full-time.

The title is theirs again. No Slam this year, but another successful campaign in which they cemented their status as the Six Nations' dominant force.

But for O'Mahony, the sweet final act of the campaign had come only after a week grappling with his involvement in the ending of Ireland's back-to-back Grand Slam bid.

Indeed, the combination of a chastening night against England and the magnitude of leading Ireland into a title decider led to nerves. A lot of them.

"I was saying to Andy [Farrell] there that it was a tough week and probably one of the toughest days I've put down nerves-wise," said O'Mahony.

"I was chatting to a few fellas there, they were in the same boat which was nice, but 100% that has to be up there as one of the most special days of my career, if not the most."

At 34 and with another gruelling season in the books, O'Mahony's future was always going to be the subject of speculation this week.

He had been coy about his future after Ireland's World Cup exit, but ultimately returned for another championship after being handed the captaincy by Farrell following Johnny Sexton's retirement.

O'Mahony's tears during the anthems before kick-off only added to the feeling that this may have been his last dance.

He played like it could have been, too, charging around the field as if hell-bent on banishing his Twickenham torment at the first time of asking.

Perhaps O'Mahony will call it a day, perhaps he won't. He was, however, clearly in no mood to overshadow Ireland's latest achievement with a definitive answer on it.

"If it was my last one, it wasn't a bad one to go out on," he said.

"I can hang the jersey in a good place, if it was. But I'll have that chat next week.

What he was definitive on, however, was what playing for his country means to him and how he savours success with Ireland given the stretches of his Test career spent watching rivals triumph.

"It's a rare feeling," admitted O'Mahony, who lifted the trophy with Tadhg Furlong, whose father passed away late last year.

I was talking to [team masseur] Willie Bennett, who's leaving us. He's been around for 35 years with the Irish team.

"He said there's been big chunks of that where we haven't been competing for championships and chunks of my career were the same.

"Last games that were dead rubbers so to be in it, to be winning championships like that is not something we'd ever take for granted."

With Sexton's retirement merely months old and with Farrell set to take a leave of absence to lead the British and Irish Lions next year, Ireland could certainly use O'Mahony's experience and leadership.

'Powerful lessons for evolving Irish'

But even if O'Mahony decides not to stick around, Ireland's future appears bright now they have moved past their World Cup misery.

Jack Crowley has a title under his belt having shouldered the burden of being Sexton's heir, while Joe McCarthy has been a revelatory - if still raw - presence in the second row.

And Farrell still has a wealth of largely untapped talent at his disposal with Ulster hooker Tom Stewart and uncapped Leinster fly-half Sam Prendergast among those who will be looking to push their way into the reckoning for this summer's Test series against the Springboks.

Ireland have experienced the two ends of the Test rugby spectrum in the past week. After the devastation at Twickenham, there was ecstasy at home.

For Farrell, coming through both will only make Ireland stronger.

"I reckon the loss last week will be the best thing for us as a group," said Farrell.

"Some of these lads, not through their own doing, have been used to winning. The special thing about the Six Nations and Grand Slams is they change week on week as we all know.

"People are fighting for their lives. For this group, some of the lads who have not been used to losing at all. I'd have to ask them but it gets to the point where they're turning up for games thinking 'we're doing it'.

"You're never doing it in the Six Nations and that Test match last week was a proper Test match in Twickenham.

"We'll learn the lessons from that and that'll be powerful for us going forward, like that one was tonight."