Orient overcame league leaders Tranmere Rovers as goals from Charlie MacDonald, his first for the club, and a cracker from Martin Rowlands lifted Russell Slade’s side up to 10th in the table.
MacDonald struck early on while Rowlands netted after the break and although Tranmere substitute Michael O’Halloran pulled a goal back for the visitors, Orient held on for a well-deserved three points and could even afford the luxury of a first-half penalty miss as they continued their climb up the table.
The Orient boss made just one change to the side that had lost at home to Southend in the Johnstone’s Painty Trophy, with striker Charlie MacDonald replacing Shaun Batt.
New signing Romain Vincelot was named on a strong bench and made his debut near the end of a thrilling encounter.
Orient made a blistering start against the title chasers as they knocked the ball about in style and carved open the visiting defence after just five minutes when David Mooney’s excellent left-wing cross picked out Lloyd James who came bursting into the box from midfield, but the midfielder, who has yet to score a league goal for the O’s, failed to make a connection.
A minute later Dean Cox’s long ball forward caught out Ash Taylor and Mooney raced cleared, but the Tranmere defender raced back and managed to block the striker’s shot.
But Slade’s side were richly rewarded for their bright start when they took the lead after just nine minutes. Cox delivered an inch-perfect free-kick from the left into the path of MacDonald and when his first effort was parried by the visiting keeper the striker, signed from MK Dons, followed up to head home the rebound from close range.
As Orient continued to press they had a golden opportunity to add a second on 15 minutes when Cox wriggled his way down the right and was bundled over by Taylor as he cut in towards goal.
Referee Trevor Kettle pointed to the spot and Rowlands took responsibility for taking the spot-kick after Mooney had seen his penalty saved at Brentford recently.
The midfielder drilled his effort to the right of Tranmere’s Welsh international keeper Owain Fon Williams, who stuck out an arm and spectacularly turned his shot over the bar.
The miss seemed to unsettle The O’s for a while, but they remained in control for the rest of the half, although despite some fine approach play they failed to create too many other opportunities.
The closest they came to the all-important second was a 25-yard blast from Rowlands, which flew inches over the bar. Then on the stroke of half-time, the veteran midfielder tried a speculative lob from 40 yards, but Fon Williams scrambled back to save inside his six-yard box.
Orient could be well-pleased with their efforts in the first 45 minutes as they spent most of the half on the front foot and dictated play for long spells, the only worry was they failed to translate their dominance into more than a single goal.
After the break Tranmere came more into the game as an attacking force and teenage striker Cole Stockton tried his luck on 65 minutes, but Jamie Jones in the home goal saved comfortably, but the pendulum was starting to swing the visitors’ way.
The game swung back the home side’s soon after however when the ball fell to Rowlands 22 yards from goal and he unleashed a left-footed drive that flew into the bottom right-hand corner of the net, to atone for his penalty miss.
That was the signal for Ronnie Moore to make a double change as O’Halloran and Abdul Bell-Baggie were thrown into the action and within five minutes the move had worked wonders.
Defender Danny Holmes raced down the right and sent a dangerous ball across the six-yard box that O’Halloran rifled home at the far post.
In a rip-roaring encounter Smith almost headed home a third for Orient following a Cox corner and 60 seconds later MacDonald fired wide. Then Mooney headed home a Cox free-kick, but the effort was ruled out for offside as O’s went for the jugular.
Tranmere made a last-gasp bid to salvage a point and Holmes sent in a rasping drive from distance, but Jones saved well and Orient held on for a well-deserved win.
Orient: Jones; Odubajo, Baudry, Cuthbert, Sawyer; Cox, Rowlands (Vincelot 85), James (J Smith 66), Cook (Batt 78); MacDonald, Mooney.
Subs: Grainger, McSweeney, Griffith, Clarke.
Goals: MacDonald (9), Rowlands (67).
Bookings: Vincelot (90+2)
Tranmere Rovers: Fon Williams; Holmes, Taylor, Daniels, Bakayogo; McGurk (O’Halloran 70), Palmer, Power, Robinson; Stockton, Amoo (Bell-Baggie 70) Subs: Mooney, Black, Goodison, Harrison, Kay.
Goals: O’Halloran (75)
Referee: Trevor Kettle
Attendance: 4,351 (inc 618 away)