Great Britain Under-18s were beaten 6-5 after penalty shots by Estonia Under-18s, despite a dramatic late equaliser from Liam Kirk with seven seconds remaining in the third period.
GB trailed 5-3 at the second intermission but Kirk scored twice to give them at least a point, before the penalty-shot heartbreak.
Britain raced into a two-goal lead after 77 seconds as Tyler Cooper fired low in the slot on the powerplay (0:32) and Rio Grinell-Parke netted on the doorstep (1:17).
Andre Linde scored a rebound (9:42) and Artemi Aleksandrov found room in front (13:21) to level the game at two each.
Britain ensured they a first-period lead when Cooper popped in a rebound at the backdoor (19:44) for his second of the night.
Estonia started the second session with two goals in less than five minutes as Grigori Barantsukov’s strike (20:50) was followed by a goal for Morten Arantez Jurgens in the slot at 24:17 (powerplay).
Rasmus Kiik finished off a short-handed break (34:33) as Estonia led 5-3 at the second intermission.
Kirk put away his own rebound after breaking free in the slot (42:04) and then tied the game in dramatic circumstances at 59:53 when he skated from one end of the ice to the other.
The Sheffield forward hit the pipes in overtime and was GB’s only scorer in the shootout, as Estonia scored twice to take the extra point.
Head coach, Martin Grubb, said: “I see this as points lost to be honest. We asked our players to come out fast, be intense and be relentless.
“We started like a house on fire. We were aggressive, we were smart and everyone looked good for the first 10 minutes to so.
“But we started to make mistakes and that second period was just horrendous.”
GB have no game tomorrow before returning to action on Tuesday when they face hosts Korea at 9pm local time (1pm UK time).