And they have lived up to their billing so far, as a 3-0 win over Kaya FC-Iloilo on Friday evening saw them set a new tournament record of 12 consecutive wins, surpassing a milestone that was set by themselves back in 2014.
Arguably the most impressive aspect of the historic result was the fact that they even managed it while resting a number of key players, as 22-year-old striker Oh Se-hun grabbed his opportunity to shine with two first-half goals that sent his side on their way.
The evident strength at manager Hong Myung-bo's disposal, and the impressive form that has taken them no time at all to find, certainly bodes well for their prospects of becoming only the second team in the ACL era to retain the crown after Al Ittihad did so in 2014-15.
Yet, while they have thus far been relatively untroubled on their way to claiming three consecutive wins over Viettel, BG Pathum United and Kaya in Group F, tougher tests will lie ahead in the Round of 16 if and when they get there, given they are far from the only team to have caught the eye.
As they have been flying the flag for South Korea, two teams have been doing the same for Japan and also currently boast a perfect record in the East Zone of the competition.
Like Ulsan, Kawasaki Frontale have claimed a maximum nine points from their first three Group I ties while Nagoya Grampus, having started their campaign slightly earlier, have won four on the trot in Group G.
Although they were fancied to progress to the knockout round, Nagoya's dominance has been fairly surprising considering they struggled for consistency prior to the tournament, winning just four out of 11 matches before heading out to Bangkok for their continental commitments.
Credit has to go to their manager Massimo Ficcadenti, who has also not been afraid to regular rotate his players given the hectic schedule, but it remains to be seen if their strongest XI can stand up against tougher opposition.
Instead, it is Kawasaki who are shaping up as the main contenders -- at least in this half of the draw -- to Ulsan's throne, as the runaway J1 League leaders look to carry over their domestic dominance into Asia's premier club competition.
Kawasaki remarkably are yet to taste defeat in any competition this year with their last defeat coming last November, and they have won a staggering 25 games out of 33 in that time.
Unlike Nagoya, Frontale also look to have considerably deeper reserves on the personnel front and have also shown a ruthless edge that is fast becoming synonymous with their game, having put 18 goals past their hapless opponents in three ACL matches so far.
Of course, performing well at this stage is never a guarantee that a team will go on to reach the final. Hitting peak form now will matter for little if these teams do not maintain into the business end of the tournament.
While they may not have captivated the attention as much, the likes of Jeonbuk Hyundai Motors, Cerezo Osaka and Daegu have all also shown glimpses to suggest they can contend should they be able to turn it up a gear in the latter stages.
But, for now, the kings of Asia are still the team to beat in the East Zone. And there is a clear standout as their primary challengers.