James O’Connor's injury-time equaliser rescued Walsall a point in a dramatic eight-goal thriller at Colchester.
Romaine Sawyers and Milan Lalkovic gave the Saddlers a 2-0 half-time lead, but Colchester hit back through George Moncur and Marvin Sordell.
George Evans restored the visitors' advantage, before strikes from Owen Garvan and Darren Ambrose put the U's 4-3 ahead.
But O'Connor fired home in the 92nd minute to preserve our unbeaten away record and keep us second in League One.
Dean Smith made two changes to the Saddlers' starting XI, with O’Connor and Andy Taylor coming in for Matt Preston and Rico Henry.
It was a breathless start to the contest with chances for both sides.
On two minutes, Craig MacGillivray’s attempted clearance was blocked by Sordell, with the ball finding Moncur, who was snuffed out by a defender.
Loanee Evans was then perfectly positioned to clear George Elokobi’s header off the line from a corner.
Walsall then went close, Anthony Forde nipping in behind the home defence but Jamie Jones stood strong to save at his near post.
Colchester were a constant threat; from one swiftbreak, Ambrose delivered a low left-wing cross which Sordell volleyed over from six yards.
After surviving that let-off, Walsall took the lead on 11 minutes, when Forde picked out Sawyers in space inside the penalty area.
The playmaker took a touch before drilling an unerring right-footed drive into the far corner.
Colchester, though, continued to look dangerous, with Alex Gilbey having a curling long-range effort tipped over by a back-peddling MacGillivray.
And shortly after, Garvan’s menacing low cross was deflected across the six yard box by O’Connor but a stretching Sordell couldn’t quite connect.
But Walsall made it 2-0 on the half-hour mark, when Lalkovic’s left-footed effort from 20 yards deflected in off a Colchester defender.
The U’s almost grabbed an immediate response but Darren Ambrose’s expertly-dispatched volley was disallowed for offside.
Home keeper Jones denied the Saddlers a third goal when he tipped over Forde’s rising drive an acute angle.
With half-time approaching, Colchester twice went close.
Callum Harriott cut inside and saw a low right-footed attempt deflect marginally wide, before Sordell fired off target from 20 yards.
HALF-TIME: COLCHESTER 0-2 WALSALL
The hosts halved the deficit within four minutes of the second half, George Moncur curling a delightful 20-yard shot into the top corner.
And the comeback was complete on 52 minutes, as Ambrose reached the byline and crossed low for Sordell to convert from close range.
Yet the Saddlers restored their lead just five minutes later.
Adam Chambers, on his 200th Walsall appearance, accurately cut the ball back for Evans to fire home first-time for his second goal in five days.
The goals continued to flow as Colchester responded immediately.
A corner was punched away by MacGillivray but only as far as Garvan, who netted with a sublime half-volley from fully 30 yards.
It was the fourth goal of an extraordinary 11-minute spell.
On 73 minutes, Harriott and Moncur combined well with the latter sweeping over from the edge of the box.
Walsall had chances of their own.
Jason Demetriou’s low drive was held by Jones at his near post and Bradshaw was inches away from connecting to Jordan Cook’s delivery.
But Colchester made it 4-3 with ten minutes remaining.
Charlton loanee Callum Harriott skipped away down the right and crossed low for the unmarked Ambrose to tap home from inside the six-yard box.
Walsall threw the proverbial kitchen sink at Colchester in the closing stages.
And the pressure told in the second minute of stoppage time, when O’Connor side-footed Kieron Morris’ centre into the roof of the net.
In a thrilling finish, Morris was then millimetres away from a 95th-minute winner when his superb long-range strike crashed against an upright.
FULL-TIME: COLCHESTER 4-4 WALSALLTeam:
MacGillivray, Demetriou, O’Connor, Downing, Taylor, Chambers, Forde (Cook 62’), Evans (Flanagan 87’), Sawyers, Lalkovic (Morris 62’), Bradshaw.
Subs not used: Jezeph, Baxendale, Preston, Kinsella.
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