When you break down the stars that aligned for Ireland's fourth Grand Slam success, it could easily be passed off as the end of a journey.

It played out like a Hollywood ending, but Ireland insist this is only just the beginning.

"They're a great group, great management team and great bunch of players," said Sexton, who broke Ronan O'Gara's scoring record, went off injured and lifted the Six Nations trophy on an eventful day for the 37-year-old in Dublin.

"I said in the dressing room that it's not the end. There's plenty more left in this team."

It's hard to argue with Sexton. While he will draw the curtain on an illustrious career after the World Cup in the autumn, the players who shone brightest during Ireland's latest Grand Slam-winning campaign suggest the team's long-term future is in safe hands under the leadership of Farrell, who is under contract until 2025.

Caelan Doris, who got the ball rolling with the first try in the opening day win over Wales, has been a colossal figure in the Irish back row.

Hugo Keenan, two years older than Doris at 26, enjoyed a sensational tournament and the fact the Leinster full-back has started 31 of Ireland's last 33 matches shows how highly Andy Farrell and the coaching staff rate him.

Ever-dependable lock James Ryan continues to grow in stature while in Mack Hansen and James Lowe they have two exciting wings with the ability to turn tight Test matches in an instant.

Then there is Ross Byrne, whose composed display in his first Six Nations start in Rome showed that he has the skills and decision-making to step out of Sexton's shadow.

They have all contributed meaningfully to a campaign in which Ireland handled everything that was thrown at them, from losing Jamison Gibson-Park to injury just before the opening match in Cardiff to the immense weight of expectation that came with the tournament's climactic chapter in Dublin.

In Cardiff, Ireland simply blew Wales away inside the opening 21 minutes. Against France, they exacted revenge for last year's Paris pain, ending Les Bleus' 14-match winning run to prevail in a tussle between the world's top two sides.

Without a host of players in Rome, and stretched at times by a vibrant Azzurri attack, Ireland still found a way to register a bonus-point win before getting over the line on a chaotic afternoon at Murrayfield when injuries forced Josh van der Flier into line-out throwing duties and prop Cian Healy filled in at hooker.

And with the Grand Slam on the line in Dublin, Ireland managed to finish the job off despite a nervy first-half performance that ignited English hopes of a major upset.

Ireland's versatility and street-smarts at the top level of Test rugby are to be admired, but Sexton insists there is much more work ahead as the World Cup in France slowly drifts into view.

"We need to keep building," warned Sexton.

"There are a lot of guys that are injured, that missed this campaign and are going to come back and really put pressure on the guys that have been playing.

"That's what we need. Come World Cup time we need 40, 45 players all at the same level, fighting for positions."

Farrell feels the same way. The 47-year-old Englishman, whose son Owen captained England on Saturday, has in the past spoken of his fascination with teams who can get to the top and stay there.

It is clear he sees considerable room for improvement. Given that Ireland could face France or New Zealand in the World Cup quarter-finals, and South Africa in the last four, it is perhaps not that surprising that Farrell wants to keep this group on their toes.

"We are a good side that has nowhere near reached its potential," insisted Farrell.

"I've been saying over the last couple of weeks that's what we have been striving to do.

"Like Johnny said, we'll get a few people back to compete, train hard. Everyone is going to get better in the summer when we get to spend more time together.

"We expect our side, when we get to the first game in the World Cup to be a lot better than what we are now and that's the reality."

'Sexton Ireland's greatest player'

It was, of course, Sexton's day, and while some will wait for the World Cup before making grand statements about his place in the pantheon of Irish greats, he was being lauded as the country's greatest ever player within minutes of Saturday's trophy presentation.

"He's been saying all week this is what dreams are made of," said Farrell. "It doesn't come around that often.

"And it's unbelievably fitting that in my opinion the best player ever to play for Ireland is able to sign off on a Grand Slam, on St Patrick's Day (weekend), in front of his own crowd.

"There are a lot of stars that have aligned over the course of the last eight weeks and come together this evening."

Farrell's sentiments were echoed by another Grand Slam winner in Jamie Heaslip, who praised Sexton's ability to handle the weight of the Ireland number 10 jersey time and time again.

"Ten in Ireland is such a lightning-rod position that causes controversy," Heaslip, who won the 2009 Grand Slam with Ireland, told the BBC Rugby Union Daily podcast.

"There was talk of 'is Johnny Sexton done?' He's had to deal with a lot of injuries along the way. You can't deny Ireland are a better side with Johnny Sexton in it.

"You have a player in Ross Byrne who has finally got his chance to be heir to the throne."