QPR needed penalties to avoid an upset in the Carabao Cup and reach the second round after eventually beating Leyton Orient 5-3 in a shoot-out.
Rob Dickie's second goal in consecutive matches appeared to put the Sky Bet Championship side on course for a routine victory, but the hosts recovered and Aaron Drinan levelled late on before Ruel Sotiriou's missed effort from 12 yards saw the hosts exit the competition.
R's boss Mark Warburton made seven changes from the weekend draw with Millwall, but one of those to retain his place opened the scoring in the 16th minute.
Dickie stooped low to head into the top corner from Faysal Bettache's corner and spark wild celebrations from the large travelling contingent, who were enjoying a first away trip since March 2020.
Orient had been second-best for much of the first half but after Drinan and Dan Happe squandered good opportunities, the former steered the ball home in the 76th minute following Tom James' long throw.
Happe poked wide again soon after and Omar Beckles smashed an effort against the crossbar, which came back to hurt the League Two outfit when Sotiriou hit the bar from the spot and Albert Adomah made no mistake with QPR's fifth penalty to secure victory.
