Argyle's youngsters can take a lot of positives from this narrow defeat to a U’s side that moved to the top of the EFL Youth Alliance table.
The result ended a run of three consecutive victories for the Pilgrims, who now have two games left to secure the top-half finish required to qualify for Merit League 1.
The game was nip and tuck until the 35th, minute when the hosts took the lead from the penalty spot, after Oscar Rutherford was harshly adjudged to have transgressed in the Greens’ area.
The second half was just two minutes old when the home side doubled their lead.
However, Argyle heads did not drop, and the Young Pilgrims went on to have the majority of the possession for the remainder of the game, forcing several free kicks and corners.
It was not until the 80th minute that substitute Jack Endacott's cross found Jamal Salawu to head home, but Argyle could not find a leveller.
Argyle: Tyler Coombes, Oscar Rutherford (Jack Endacott 75), Ali Mansaray, Oscar Halls, Ethan Mitchell, Brandon Pursall, Carlo Garside, Charlie Miller, Angel Waruih, Oscar Massey, Jamal Salawu. Substitutes not used: James Morley, Jeffery Forkuo.