Great Britain's men gave away a two-goal advantage in their opening match of the Sultan Azlan Shah Cup as hosts Malaysia struck twice in the last three minutes to secure a 3-3 draw.
Jason Lee's side were well worth their 3-1 half-time lead and looked like holding on for three points in the six-team tournament only to have their resolve broken late on.
"We're pleased with how we played in the first half and we had enough chances in the 15 minutes after half-time to put the game beyond Malaysia," said Lee. "But as expected in the dying minutes the heat became a factor and in the end the game was five minutes too long for us."
East Grinstead midfielder Glen Kirkham's fifth-minute opener was quickly cancelled out by Azlan Mizron from a penalty corner routine.
Two goals in five minutes put GB into a commanding position as first Ashley Jackson, scoring his 70th goal in 127 international appearances, and then Surbiton's Rob Moore struck.
In the second half captain Barry Middleton beat the goalkeeper but not the bar with a clever chip but as GB tired in the hot conditions Faisal Saari scored twice to level the scores.
GB face India, whom they beat twice in the Olympic test event earlier this month, on Sunday.