Substitute Miles Mercury was the young O’s hero as his late strike saw them come from behind to pick up a 3-2 win over Plymouth Argyle.
Peter Gill’s side were 1-0 and 2-1 down during the second period, but kept going and scored twice in the space of four minutes to seal a Merit League One victory.
It was a cagey opening period as the heavy wind caused problems for both sides, but O’s goalkeeper Sam Roach launched a number of good Orient attacks throughout.
Roach’s opposite number Max Childs was the busier of the two keepers though in the first period, making two good saves.
Charles Clayden was through one-on-one with the goalkeeper but was unable to make the most of the effort as he shot straight at Childs, before the Plymouth shot-stopper did well to expertly tip another effort wide with 15 minutes on the clock.
A scrappy first half ended goalless, but the second half was much more eventful and the visitors took the lead against the run of play as they capitalised on a defensive mistake to break the deadlock.
Despite the setback the O’s continued to dominate and create a number of opportunities, however, it took until the 75th minute for Orient to draw level and it came through skipper and defender Dan Happe.
The centre half brought the ball out from the back, and in similar fashion to first teamer Tom Parkes against Doncaster Rovers, he kept his run going into the area and he coolly slotted home to level matters.
Parity did not last long though as with eight minutes left on the clock Plymouth once again went in front and the O’s would have to do it all over again.
But the youngsters never know when they are beaten and the in-form Ruel Sotiriou was on hand to find a second equaliser with five minutes remaining.
A ball over the top dropped over the shoulder of the striker before he produced a stunning volley to give Childs no chance in the Pilgrims goal.
The action didn’t end there though and with two minutes to go the O’s went in front for the first, and most important time.
Some good play down the right hand side resulted in Amin Benyoucef producing a superb defensive splitting pass in the area to find substitute Mercury who was able to blast home with a cool and composed finish.
Orient saw out the remaining minutes solidly to pick up a welcome victory and are next in Merit League One action when they travel to Exeter City on April 8.
ORIENT: Sam Roach, Andrew Camilo-Tayaca, Toby Stevenson, Hector Kyprianou (Jaedon Phillips 55), Mason Hall, Dan Happe, Aaron Rowe (Amin Benyoucef 55), Pat Adamson, Ruel Sotiriou, Sam Dalby, Charles Clayden (Miles Mercury 70)
GOALS: Happe, Sotiriou, Mercury