Ange Postecoglou will never have a better chance to win a continental club championship than in 2020 but that dream is now over after a surprise 3-2 loss to the unfancied Suwon Bluewings in Qatar.
The former Socceroos boss and his Yokohama F. Marinos had been in a fine position on Tuesday (AEDT).
The Japanese champions had strolled through the group stage, swatting aside Jeonbuk Motors of South Korea, a perennial ACL powerhouse.
In Qatar, where the eastern zone of the continental competition resumed after eight months, Jeonbuk were missing a number of players and were not at their strongest or best.
Yet even when they were, back in February, they lost 2-1 at home to Yokohama.
It was a result that flattered the hosts and there was plenty of surprise and admiration about the Japanese champions even before they went on to beat Jeonbuk 4-1 last week.
According to officials at the Korean club, Yokohama’s name was on the trophy as they were head and shoulders above the rest - the best team Jeonbuk had seen in Asia for years, so they said.
As well as Jeonbuk in the group stage, there was Shanghai SIPG, a team with almost $200 million worth of signings in Hulk and Oscar, not to mention Aaron Mooy.
Then there was Sydney FC, the best team in Australia by some distance. The Marinos strolled through in impressive style, finishing top with a margin of four points.
The Kanagawa team had won the 2019 J1 League title in impressive fashion but they struggled for consistency at home in the 2020 season.
On their day however, they were more than a match for anyone and that is all that is needed when it comes to the Champions League - where, this year, there are just three single games before the final.
Never has the route to the top of Asia been shorter.
Playing Suwon in the round of 16 held few fears. If Jeonbuk were champions of Korea, Suwon had spent most of the K-League season worried about relegation, finishing just six points above the bottom team.
Not only that, the Bluewings arrived in Qatar with a young squad, missing experienced stars such as Yeom Ki-hun and all of their foreign contingent, including Australian stars Adam Taggart and Terry Antonis.
Yokohama were strong favourites to win and, then with Suwon out of the way, were still favourites against Beijing Guoan and Ulsan Horangi.
The 2019 J1 League champions were more than capable of negotiating such challenges and earning the right to take on Persepolis of Iran in the final on December 19.
There are no guarantees in tournaments, especially those as unpredictable as the AFC Champions League, but Yokohama were the team to beat.
Yet they beat themselves. Against Suwon on Tuesday, the Japanese team took the lead and were looking good to extend it at any time, but chances were missed.
Perhaps there was a feeling that the job was done, perhaps there was some underestimation of Suwon, but Yokohama became sloppy in possession and, as has often been the case this season, sloppy at the back.
As more opportunities were spurned, it became almost inevitable that Suwon would score - and so it came to pass - but few would have expected the Bluewings to take a 3-1 lead.
That two-goal cushion meant that Yokohama’s second goal, coming in injury-time, was a mere consolation.
It means that Suwon continue on their surprise path towards a possible third Asian championship.
Yokohama, however, have yet to win one but, as they, and their coach, fly back east, they will be kicking themselves at missing a perfect opportunity to take the continental crown.
It would have given Postecoglou another major title to go along with the Asian Cup won with Australia in 2015, as well as the A-League and J1 League titles.
Now, he will have to wait. How long remains to be seen.