The 24-year-old marked his senior international debut by converting all five of Ireland's tries and knocking over a brace of penalties in a commanding individual display that won plaudits from both the Irish and Fijian coaching staff.
"I was impressed by Ireland's number 10," said temporary Fijian coach Glenn Ella, after his side lost to a Celtic nation for the second week running following a 23-10 reverse at the hands of Scotland seven days earlier.
"He has a bright future for many years to come."
Thos sentiments were echoed by Irish boss Declan Kidney, who was equally impressed with the way in which Sexton took over the playmaking duties from veteran international Ronan O'Gara.
"Jonathan showed great maturity out there," said Kidney, as Ireland remained unbeaten in 2009 to date.
"Then again, I'm not surprised. Last year, when things were not going so well for him, he stuck at it, which is a great sign."
There were plenty of positive signs for the Ireland team as a whole as well, with a much-changed starting XV showing there is substantial depth in Irish rugby at the moment.
Munster's Keith Earls crossed for Ireland's only score of the first 40 minutes as the hosts held at 13-3 lead at the break.
But it was largely one-way traffic after the interval as skipper Brian O'Driscoll, Earls and Leinster duo Rob Kearney and Shane Horgan all added to Ireland's score in their first-ever international at the RDS.
Next up for Ireland are World Champions South Africa at Croke Park on Saturday, with an Irish win set to make it a hugely satisfying way to end an historic international season for Kidney and co.
Ireland: Rob Kearney, Shane Horgan, Brian O'Driscoll (captain), Gordon D'Arcy, (all Leinster), Keith Earls (Munster), Jonathan Sexton, Eoin Reddan (both Leinster); Tom Court (Ulster), Jerry Flannery, J Hayes (both Munster), Leo Cullen (Leinster), Paul O'Connell (Munster), Stephen Ferris (Ulster), Denis Leamy (Munster), Jamie Heaslip (Leinster)
Replacements: Sean O'Brien (Leinster) for Denis Leamy 44; Tomas O'Leary (Munster) for Eoin Reddan (55); Tony Buckley (Munster) for John Hayes 60; Andrew Trimble (Ulster) for Brian O'Driscoll 68; Donncha O'Callaghan (Munster) for Paul O'Connell 68; Sean Cronin (Connacht) for Jerry Flannery 73; Paddy Wallace (Ulster) for Rob Kearney 75
Guinness PRO12
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