TWO goals in the final eight minutes condemned Argyle to their second EFL Merit League One defeat as they are left still looking for their first victory in the competition.
"Conceding two late goals was very disappointing especially after twice taking the lead," said Argyle Academy Manager Kevin Hodges.
Argyle gave a debut to young defender Kai Cornish but he unfortunately sustained an early injury and had to be replaced by Oliver Tomlinson, who was also making his debut, after just eight minutes.
The first half was goalless despite Argyle having the wind at their backs but the second period was only five minutes old with Alex Battle released Dan Rooney to fire low past the home goalkeeper for a cool finish.
Orient levelled on 76 minutes when a striker's shot flew into Max Child's net via the inside of the post but Argyle had restored their lead four minutes later. Good play by Battle put in Alex Fletcher who saw his initial effort well saved by the 'keeper but the Argyle top scorer followed up to head the loose ball home.
Unfortunately that elusive first victory was not to be as Orient struck twice, in the 82nd and 85th minutes, to snatch victory from the jaws of defeat.
Argyle: Max Childs, Kai Cornish (Oliver Tomlinson 8), Harry Downing, Elliott Crawford, Ryan Law, Matt Ward (Michael Peck 85), Dan Rooney, Cameron Sangster (Rio Garside 85), Billy Craske (Aaron Goulty 85), Alex Fletcher, Alex Battle.