Belfast Star coach Adrian Fulton described his side's 96-89 overtime defeat away to Moycullen as "the worst performance of the season by a mile".
Star were knocked off top spot in the All-Ireland Superleague as Tralee maintained their relentless drive to retain the title with a one-point victory away to Templeogue on Saturday night.
The Belfast men had the game in their grasp, leading by two points with only two seconds to go, but somehow allowed American Daniel Vila to tie it at 78-78, leaving Fulton fuming and the Moycullen fans in a frenzy.
The momentum had swung the way of the home side and they turned the screw with some fine scoring from James Connaire, Conor Curran and Vila.
American Delaney Blaylock top scored for Star on 39 points but his performance was not matched by his team-mates.
Fulton said: "There were so many things that I could talk about. It was just the worst performance of the season and then to seemingly get ourselves out of jail and then allow them to score a simple basket with two seconds to go was just awful. Schoolboy errors let that happen.
"We've already had a good talk about the performance and we all have to learn from it. The only good thing is that the last time we had a performance like that, when we were beaten at home by Eanna in the Cup, we then went six games unbeaten."
The defeat leaves Star three points behind Tralee, though the defending champions do have a possible six-point deduction hanging over their heads, which they are expected to appeal.
Fulton added: "We just have to focus on ourselves and Killorglin this Saturday night at home."