Since Asian football's revamp of its club competitions saw a reduction of teams contesting the top tier with the introduction of the AFC Champions League Elite at the start of the 2024-25 campaign, only two spots -- at present -- have been allocated to Southeast Asian clubs.
In two editions, it has been Malaysia Super League's Johor Darul Ta'zim and Buriram United of Thai League 1 representing the region.
And, on Tuesday, the duo once again flew the flag for the region by securing a top-eight finish in the East region of the league stage -- and a place in the round of 16.
Buriram, who started the day 5th and as the highest-ranked team yet to seal their progress, were in a stronger position but would waste no time in making sure they would be advancing with a 2-0 win over Shanghai Shenhua.
It took them 11 minutes to open the scoring when Curtis Good evaded the attentions of his marker to meet a Peter Žulj corner with a glancing header into the bottom corner.
Eight minutes before the half-hour mark, the same scenario had a similar end result even if it may have arrived in different fashion - with Žulj's delivery from the same end of the field cleared but only as far as to just inside the area, where Suphanat Mueanta coolly took the ball down on his chest before firing home with a sumptuous left-footed effort on the bounce.
The contest was effectively over in the 33rd minute when Shenhua were reduced to ten men after Rafael Ratão received a second yellow for a stray elbow into the face of Good -- incredibly just two minutes after his first caution.
Nonetheless, things were far less straightforward for JDT, who began the day 7th and aware that three teams below still had a realistic chance of overtaking them.
It also did not help they were finishing the league stage against table-topping Vissel Kobe, although their cause was aided by the fact that the Japanese visitors -- as expected -- opted to rest almost their entire strongest XI.
Still, an undermanned Vissel outfit still offered plenty of resistance and were arguably the better team in the first half -- with JDT having a couple of close shaves.
The Southern Tigers did eventually find their footing and though they had broke the deadlock in the 39th minute through a clinical finish by Nené -- only for the strike to be ruled out upon VAR review as the delivery from Hector Hevel had come from an offside position.
The hosts were to be denied once more 11 minutes after the restart when Marcos Guilherme just failed to stay onside before latching onto a lovely poked pass from Bérgson to slot past Shūichi Gonda, with the linesman's flag sufficient intervention on this occasion.
Nonetheless, JDT's persistence finally paid off in the 73rd minute -- just a minute after they had the woodwork to thank for Vissel not edging ahead at the other end.
Substitute Jairo deserves plenty of credit with some classic target-man play to keep a clearance from goalkeeper Andoni Zubiaurre in a forward trajectory from a 50-50 aerial duel -- and then legally dispossessing Boniface Nduka just outside his own area after the latter had reached the loose ball first.
Although Jairo would have been well within his rights to advance into the area on his own, he instantly slid a pass across to the rampaging Guilherme, who would finally get his goal with a low finish past Gonda.
Despite a nervy end to the contest, which included another Vissel effort that was only kept out by the woodwork, JDT were ultimately able to hold out for a 1-0 win.
Last season, their final positions on the table meant that they would face off in the round of 16. It guaranteed at least one Southeast Asian team would be contesting the centralised finals -- starting from the quarters and culminating in the decider in a whirlwind tournament -- in Saudi Arabia, but it also meant that there was no way there could be two.
This term, Buriram can only drop as low as fifth while JDT can no longer finish any higher than 6th, thus ruling out a repeat of that situation.
For JDT, especially, it means they will likely face a daunting task against one of the three Japanese high-fliers in Vissel, new leaders Machida Zelvia and Sanfrecce Hiroshima -- with only Melbourne City a chance to break up the J1 League's monopoly on the top spots.
Buriram will either face City or Sanfrecce, with the ties only to be determined on Wednesday when the league stage officially comes to an end.
Time will reveal who will be next in the way of Southeast Asia's hopefuls in their quest for continental glory but, for now, they have both taken the first step in once again flying the flag for the region.