Only twice in the club's 125-year history have they previously secured European football in the group stage, but 2024 has now been added to that list after a thrilling extra-time win over Slovenian champions NK Celje.
History made. First time Rovers do it on home soil. Conference League group stage football secured, and a Europa League play-off in the bag. A guaranteed €3.8 million in UEFA prize money. Hoops supporters, get your passports ready for this winter.
Rovers will now face Greek champions PAOK for a place in the Europa League (first leg away), with football in the Conference League already guaranteed.
With a 1-0 deficit to turn around, Rovers scored twice in four minutes to give themselves the advantage as Dylan Watts' cool first-half penalty was closely followed by Neil Farrugia's spectacular long-range strike. Farrugia, Watts and Rovers captain Roberto Lopes in particular produced performances for the ages.
A late goal from Slovenia international Zan Karnicnik forced extra time before substitute Graham Burke scored the vital winner to blow the roof off Tallaght Stadium. Darragh Burns' strike was ruled out by VAR for offside.
Stephen Bradley's men had two excellent chances to score before Celje equalised through Trevor Clarke and Josh Honohan, but they eventually pulled through to cap off a remarkable night for the Irish League after Stephen Kenny's St Patrick's Athletic finished the job in Baku to secure a Conference League play-off spot.
After a minute's silence in memory of the late Jim McLaughlin, who led the Hoops to three consecutive league titles in the 1980s, the hosts got off to a brisk start.
Among the 6,153 spectators were former Rovers players Gavin Bazunu and Danny Mandroiu. Former Ireland Under-21 player Farrugia also tried to find Aaron Greene early in the game but the through ball was mistimed, while 25 travelling Celje supporters dressed in black T-shirts made their voices heard.
The visitors, led by former Spain and Liverpool player Albert Riera, were soon calmed down, however, with Armandas Kucys denied by an excellent block from Rovers' Lee Grace, who had come into the starting line-up. This was Bradley's only change from the first leg last week.
Greene scored the decisive goal in the 37th minute when 19-year-old Celje goalkeeper Lovro Stubljar attempted to clear a long ball. He came off his goal to tap the ball away, but instead fired the ball past Rovers' striker in the penalty area.
The Romanian referee initially signalled for a free-out before VAR advised him to consult the pitchside monitor. Tallaght waited with bated breath and cheered as he pointed to the spot. Watts stepped up, sent the keeper the wrong way and slotted home the penalty with aplomb.
The ground erupted again when, barely four minutes later, Farrugia began an excellent raid, gliding past a couple of blue and yellow shirts with ease. With a quick glance upwards, the winger found the bottom corner with a truly brilliant strike from 25 yards. For the first time in this round, the advantage was Rovers.
The one-goal lead should have quickly become two when Farrugia passed the ball to Clarke seconds before half-time, but the wing-back was denied his first European goal by a superb close-range save from Celje's number one.
Slovenian international Karnicnik levelled the score seven minutes from time with a beautiful volley at the far post. A few seconds later, however, it could have been even worse, as Grace had to clear an effort off the line and extra time brought the equaliser.
Six minutes later Burke took possession near the halfway line, stepped up and found the net from just outside the penalty area. It may have been a gift from Celje's young keeper, but Tallaght didn't care. The Irish striker scored his ninth European goal to swing the equaliser back in Rovers' favour.
Burns had his goal ruled out for offside in the 106th minute, but Rovers held on to see the equaliser go in. The final whistle brought an explosion of sheer relief and joy. For the second time in three seasons, Rovers had done it.
“I would say we are better than the opposition,” a confident Riera claimed on the eve of this second leg. They had to work hard for it, but Rovers did their best on the pitch to make it a special night in Dublin 24.
Shamrock Rovers: Pohls; Honohan (O'Sullivan 110), Grace, Lopes, Hoare, Clarke (Cleary 80); Watts, O'Neill; Nugent (Towell 80), Farrugia (Burke 88); Greene (Burns 91).
NK Celje: Stalker; Vuklisevic, Zec, Nemanic (Karnicnik 46); Brnic (Menalo 46), Kvesic (Aarons 104), Bobicanec (Dulca 46), Kavcic; Matko (Edmilson 79), Kucys, Pisek (Kouter 53).
Reference: Ovidiu Hategan (Romania).