Democratic Republic of Congo came from two goals down to progress to the semi-finals of the Africa Cup of Nations with a 4-2 victory over neighbours Congo in Bata, and host nation Equatorial Guinea also reached the last four after an extra-time win against Tunisia.
Congo, competing in the quarter-finals for the first time since 1974, looked to have provided yet another shock by reaching the last four after goals from Ferebory Dore and Thievy Bafouma had given them a comfortable lead with just half an hour remaining.
But DR Congo launched a spirited fightback and quick-fire strikes by Dieumerci Mbokani and Jeremy Bokila restored parity before Joel Kimuaki turned the contest on its head by bagging a third nine minutes from time.
Mbokani then added his second of the match deep into stoppage time to complete a stunning turnaround and send DR Congo through to their first semi-final in 17 years.
DR Congo will be joined in the semi-finals by Equatorial Guinea after they defied the odds once again with a dramatic 2-1 win over Tunisia after extra-time.
Tunisia, ranked 96 places above Equatorial Guinea in the FIFA world rankings, couldn't quite assert their attacking advantage during the contest although they did take the lead after 70 minutes as Ahmed Akaichi turned home a teasing delivery from Hamza Mathlouthi.
Just as it looked as though Tunisia would progress, the hosts were awarded a penalty in second-half stoppage time after Ivan Bolado was fouled in the box and Javier Balboa demonstrated immense composure by converting the spot-kick to send the game into extra-time.
Equatorial Guinea were clearly spurred on buy the now raucous home crowd and Balboa then bent a beautiful free-kick into the top corner after 102 minutes.
Tunisia threw everything at the National Thunder but they couldn't breach a valiant back line and the host nation saw the match out to book their semi-final berth, sparking delirious scenes inside the stadium.
DR Congo will face either Ivory Coast or Algeria, while Equatorial Guinea will entertain either Ghana or Guinea.
In what has been a fairly tepid tournament to date, the clash between two fierce rivals in DR Congo and Congo provided the spark the competition needed.
After a largely uneventful first half, the match livened up after the restart and Bokila should have given his side the lead but he contrived to strike the crossbar from close range.
DR Congo were made to rue that guilt-edge chance as the Red Devils went ahead shortly after when Dore sprung the offside trap before coolly slotting home from point-blank range.
Just seven minutes later, Congo doubled their lead as Dore caused havoc in the box and his shot was blocked on the line but the rebound fell kindly for Bifouma, who lashed the ball into the net to send his team mates into delirium.
The celebrations proved premature though as DR Congo responded quickly to halve the deficit as Mbokani converted a Yannick Bolasie pull-back.
The Leopards were clearly buoyed by Mbokani's goal as they went in search of an equaliser with renewed vigour, and it came after 75 minutes when Bokila found the roof of the net with a superbly-struck shot to level proceedings at two apiece.
However, the drama wasn't over by a long shot as Kimuaki glanced home a teasing set-piece from Cedric Mabwati to swing the pendulum the way of DR Congo.
As Congo pressed forward looking for a leveller of their own, Florent Ibengé's men launched a swift counter-attack which was finished well by Mbokani to seal an incredible comeback victory for his side.
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