The Kerry star’s day began with a goal inside two minutes and finished up with a black card nine minutes into injury-time of a game that lasted nearly 80 minutes in total.
In between, the former All-Ireland winning Kingdom captain suffered a dead leg that will concern county supporters, traded shoves with a Rock mentor and took his tally to 1-3 for the day with two late insurance points.
It was one of those zany afternoons and the sight of O’Sullivan hobbling around the full-forward line throughout the second-half can’t have been too pleasing for Kerry manager Eamonn Fitzmaurice.
The suggestion from both player and manager afterwards was it wasn’t a major flare up and that the 30-year-old may only be sidelined for a couple of weeks.
As for Rock, it was their second loss at this stage since 2008 and they finished the game with 12 men after three dismissals.
A couple of their own players even grappled with each other on the way off the pitch at half-time on what was a frenzied afternoon.
Glenbeigh-Glencar lost a man to a red card on what was a reprise of any number of bruising battles between Kerry and Tyrone teams over the last 15 years or so.
Victorious manager Aidan O’Shea said he expected the war of attrition.
“Oh we expected it to be tough and hard alright,” said O’Shea.
“I thought some of the decisions were maybe to the letter of the law a small bit. But it was a very tough game. It wasn’t unbelievably dirty but there were still four sendings off which is an awful lot for a game.
“It was probably the hardest game we’ve had, physically. They’re a really hard team to play against and they were mentally tough as well.”
That Glenbeigh-Glencar had enough about them to pull through, closing out the win with the last three points of the game from Bernard Murphy, O’Sullivan and Jason McKenna, was particularly pleasing to O’Shea.
“We were only going to get one chance at this,” he continued.
“We’ve been unlucky in junior championships in Kerry before but a lot of people were...look, people would have been talking about it back home that we couldn’t close out the deal in Kerry so to come along and win the All-Ireland brings a bit of closure to that. That chapter is behind us now, the near misses we’ve had.”
And yet there was that nagging feeling that after the brightest of starts Glenbeigh-Glencar may be in trouble again.
An early 1-1 burst from O’Sullivan opened up a four-point advantage, the exact margin that bookmakers tipped the Kerry side to win by.
But that was wiped out by half-time as Rock, with former Tyrone star Ciaran Gourley and Conor McCreesh impressing, imposed themselves on the game to leave it 1-6 to 0-9.
Rock were reduced to 14 men after 22 minutes when Enda McWilliams received his second booking for a heavy hit on O’Sullivan.
The numerical advantage lasted just minutes for Glenbeigh-Glencar who lost Daniel Griffin to a straight red card for an off the ball incident just moments after he was denied a penalty.
A scuffle broke out as the players exited the pitch for half-time and the ill temper continued with a Rock mentor, who’d entered the pitch in the 43rd minute during a break in play, clashing with O’Sullivan.
He shoved O’Sullivan who responded in kind before the duo went head to head. The mentor was eventually dismissed to the stand.
“It was bizarre,” recalled O’Shea.
“I didn’t see it but when I turned around I knew what happened. Obviously there was a bit of an altercation. Look, I’d say the same man wouldn’t have entered the field if he had his time over again. But I don’t think there was a whole pile in it.”
By now, O’Sullivan was visibly hobbling, having picked up a dead leg while attempting to turnover possession late in the first-half. The idea of taking him off and potentially throwing him back in late on was considered but rejected.
Rock got a lifeline when Padraig Ward capitalised on good work by Thomas Bloomer and Eamon Ward for a 49th minute goal that put them 1-10 to 1-8 ahead.
But they only scored one more point as Glenbeigh-Glencar answered any questions about their ability to close out tight games by scoring six of the game’s last seven points.
O’Sullivan was excellent, conserving his energy before taking off on one great run that yielded a fisted point, putting his team two ahead.
McKenna and Murphy hit excellent late scores too while Gavan O’Grady arguably showed most character of all, bouncing back from a number of bad wides to hit six points.
G O’Grady (0-6, 3 frees); Darran O’Sullivan (1-3); K Courtney (0-2); F Griffin, B Murphy, J McKenna (0-1 each).
A McGarrity (0-5, 4 frees); P Ward (1-0); C McCreesh (0-3); C. Gourley, D Carroll, A. Girvan (0-1 each).
R O’Connor; S O’Sullivan, C Doyle, J Hoare; J Brosnan, P Kilkenny, C Teahan; C McGillycuddy (c), F Griffin; Danny O’Sullivan, Darran O’Sullivan, T Cahill; K Courtney, G O’Grady, D Griffin.
B Murphy for Cahill (50); V Hoare for F Griffin (60); J McKenna for Danny O’Sullivan (60); P Griffin for Darran O’Sullivan (69, black card); D McGillycuddy for S O’Sullivan (71).
S Donaghy; N McWilliams, N Mullan, M McAleer; C McWilliams, A Girvan, S Mullan; C Gourley, D. Carroll; E McWilliams, E Ward, T. Bloomer (c); C McCreesh, A McGarrity, R Crilly.
P Ward for Mullan (19); D Reid for N McWilliams (33); L Nugent for C McWilliams (53); C McWilliams for E Ward (65); S Litter for McGarrity (71).
J Henry (Mayo).