Two goals in as many first half minutes saw 10-man Orient fall to a 2-0 home defeat to Wycombe Wanderers.
A promising start from the O’s ended when Tom Parkes was shown a straight red card for a challenge on Garry Thompson, before Matt Bloomfield and Myles Weston quickly put the Chairboys in command as Omer Riza’s first game in charge ended in a loss.
Riza made four changes to the side which lost 3-0 at Crawley Town last weekend with Michael Collins, Teddy Mezague, Rowan Liburd and Jens Janse coming into the starting line-up.
The O’s bench consisted solely of Academy products, with the latest seeing first year scholar and goalkeeper Arthur Janata on the bench with Alex Cisak and Charlie Grainger ruled out through injury.
Luke O’Nien warmed the hands of Sargeant early on but the O’s started positively and Koroma forced Jamal Blackan in the Chairboys goal to save with his legs after some good link up play with Liburd.
Orient remained on the front foot and only an intervention from Myles Weston denied Teddy Mezague’s header from a corner.
From their very first corner of the game the visitors went close when Saunders’ teasing inswinging delivery found the head of Will De Havilland but the defender glanced the effort over the bar.
Orient continued to look bright going forward and only a deflection denied the lively Koroma the opener on 10 minutes.
The game remained open and Sandro Semedo tried his luck from distance and forced Blackman into a strong push before Orient won another corner which came to no avail.
Another fluid move saw Koroma not quite able to get a decisive touch on the edge of the box, but the signs were encouraging for the hosts.
But the game changed in the Chairboys favour when Tom Parkes was shown a straight red card with 27 minutes on the clock. The defender was adjudged to have gone in too high on Garry Thompson and referee Charles Breakspear wasted no time in getting the red card out of his pocket.
If the O’s had any luck this season it was certainly no luck and the Chairboys broke the deadlock when the ball fell kindly to Bloomfield in the six-yard box and he slotted past Sargeant on 37 minutes.
One soon became two as a minute later the visitors found themselves further ahead in controversial circumstances.
Janse was shepherding the ball back to Sargeant when Myles Weston appeared to push the defender into the goalkeeper.
The ball wriggled free and Weston tucked home, and despite strong appeals from the home fans and players, Breakspear opted to allow the goal to stand.
That brought to an end an interesting half and although neither side made any changes at the break, Riza was forced to watch the second half from the stands after also being dismissed by referee Breakspear.
Bloomfield sliced a shot wide in the early stages of the second period, before the whole crowd gave a round of applause in memory of O’s fan and Mr Orient Frankie Bish who was tragically killed on Thursday.
Harriman fired a shot into the side netting and then Luke O’Nien tried his luck to no avail with a header over the bar.
The O’s first chance of the second period came on 63 minutes when Kelly did well to work an opening for Liburd but his shot was saved by Blackman, before Sargeant produced a top save to deny a fine curling effort from Sam Saunders.
Orient tried to go for it when bringing on Tristan Abrahams for Janse, but chances continued to be few and far between against the side with a man advantage.
The hosts kept going though and Blackman denied Abrahamas a first time effort with 13 minutes remaining, while Semedo fizzed over shortly afterwards.
Chances were few and far between in the closing stages as the O's lost out at home ahead of next weekend's trip to Cambridge United.
LEYTON ORIENT: Sargeant; Mezague, Parkes, Hunt; Kennedy, Kelly, Collins, Janse (Abrahams 65); Semedo, Koroma (Alzate 80), Liburd (Dalby 73)
SUBSTITUTES: Janata, Moncur, Ochieng, Clark
12TH MAN: Frankie Bish, Mr Orient
BOOKED: Semedo (45), Collins (75)
SENT OFF: Parkes (27)
WYCOMBE WANDERERS: Blackman, Jacobson, Pierre, De Havilland, Harriman, O’Nien, Bloomfield (Gape 89), Thompson, Weston (Wood 79), Saunders (Freeman 72), Akinfenwa
SUBSTITUTES: Richardson, Jombati, Hayes, Kashket
GOALS: Bloomfield (37), Weston (38)
REFEREE: Charles Breakspear
ATTENDANCE: 4,526 (766 Wycombe Wanderers fans)