But the O's only had themselves to blame for this latest setback as some abysmal defending cost them dear.
Skipper Gary Alexander and Daryl McMahon almost threw Orient a lifeline with late goals but it was not enough to patch up their defensive frailties.
The home side's misery started early as 16th minute when Joe Keith and gave Ali Gibb too much space and his pinpoint cross from the right found Craig Disley in splendid isolation at the far post and the midfielder headed sweetly home.
Orient huffed and puffed in a bid to get into the match and Alexander had two efforts blocked but Rovers always threatened on the break and home goalkeeper Glyn Garner superbly denied Agogo as he pushed away his curling effort midway through the half.
Orient changed their system at half-time with Shane Tudor replacing Donny Barnard and they pushed hard for a leveller with McMahon going close but they pressed the self-destruct button as the ever dangerous Agogo outpaced Joe Dolan before John Mackie pulled him down.
Ref Mick Russell pointed to the spot and Agogo picked himself up and sent Garner the wrong way to extend Rovers' advantage.
Orient stepped up the pace in a bid to get back into the game but were denied time and time again by a resolute Rovers defence before Keith's persistence paid dividends and when the ball fell to Justin Miller his cross was volleyed home by Alexander.
Orient went in search of a leveller but paid the price for conceding possession from their own corner and Agogo's pace took him past McMahon before he beat Garner and slotted home a third.
Orient refused to throw in the towel and McMahon fired home through a crowd of players a minute from time but it was too little too late.