Jobi McAnuff opened the scoring with a calm finish in the 19th minute, though Hartlepool levelled in first half stoppage time through Jonathan Franks before Rhys Oates’ 47th minute header clinched all three points for the visitors.
With the O’s looking for a strong response to Tuesday night’s home defeat to FC Halifax Town, Head Coach Steve Davis made three changes to the starting XI.
Dan Happe was handed a first appearance of the season in the centre of defence, as Michael Clark dropped to the bench, while Josh Koroma and David Mooney also came into the side.
Romuald Boco was also named among the substitutes after starting against Halifax, though Matt Harrold was sidelined due to injury meaning a first inclusion for striker Sam Dalby in the matchday squad.
With the BT Sport cameras in E10, both teams battled for early dominance and with the 10 minute mark approaching Macauley Bonne pounced on a ball in behind the defence only to be denied by Pools ‘keeper Scott Loach as the flag was raised offside.
David Mooney then reactly smartly after earning a free-kick moments later, and opted for an early pass to release Jobi McAnuff in the area who then saw his cross towards Bonne intercepted.
As the O’s continued to grab a foothold of the tie, Loach was then on hand to hold a Mooney shot after the Orient skipper had turned well outside the box.
The hosts dominance was then rewarded on the 19th minute, as a lovely pass from Koroma played in Mooney. After lining up a shot the Irishman was once again thwarted by Loach, though McAnuff was in the right place to sweep home the rebound from the edge of the box.
The lead was a deserved one, and cold have been a two-goal advantage on the 25th minute as Alex Lawless clipped a pass for Bonne who drilled a shot beyond Loach only for it to come back off the post.
Following that, the O’s failed to really trouble Loach any further in the visiting goal as several low crosses into the box were cleared by the Pools defence.
Three minutes’ stoppage time was then shown by the fourth official, and with one played Hartlepool managed to find an equaliser as Jonathan Franks rifled home inside the box.
Franks’ strike meant that the sides went into the break all square, and following the interval Orient returned unchanged, though Hartlepool got off to a fast start and turned the game on its head as Rhys Oates’ 47th minute header gave Pools the lead.
Rocked by the goals either side of the break, Orient were then almost dealt a further blow on the 53rd minute as Ryan Donaldson’s shot took a deflection off Joe Widdowson to curl beyond the reach of Charlie Grainger before coming back off the post.
Bonne had been lively for the O’s throughout the first half, and the forward came close to forcing an equaliser moments later as he managed to break into the Pools box before seeing his left-footed shot palmed away by Loach.
Koroma was next to come close as his shot from a corner flew over the bar, and with 25 minutes remaining Orient made their first change of the afternoon as Sam Dalby came on in place of Mooney who had been struggling from a shoulder injury sustained in the first half.
Within three minutes of his introduction Dalby looked to have played a hand in an equaliser, threading a pass through to Koroma who calmly slotted beyond Loach only for the goal to be ruled out for offside.
Hartlepool were proving stubborn to break down after taking the lead, and with just over 10 minutes remaining the O’s were forced into a second change of the afternoon as Craig Clay limped off to be replaced by Henry Ochieng.
Despite enjoying most of possession, Orient were unable to get beyond a stubborn Hartlepool backline, with an Ochieng cross dropping just wide of the post before five minutes stoppage time was shown.
Searching for that elusive equaliser, Lawless clipped a ball back into the box following a McAnuff corner but Bonne could only find the side-netting as Hartlepool held on for the victory.
ORIENT: Grainger, Caprice, Sendles-White, Happe, Widdowson, Lawless, Clay (Ochieng 81), Koroma (Boco 86), McAnuff, Mooney (C) (Dalby 65), Bonne
SUBS: Sargeant, Clark
GOALS: McAnuff (19)
BOOKED: Mooney (29), Lawless (54), Caprice (88)
HARTLEPOOL: Loach, Magnay (C), Watson (Laing 90+6), Ledger, Deverdics, Featherstone, Hawkins, Woods, Donaldson, Franks, Oates (Rodney 72)
SUBS: Munns, Donnelly, Newton
GOALS: Franks (45+1), Oates (47)
REFEREE: Carl Brook
ATTENDANCE: 3,867 (208)