Cairo - Famed Egyptian club Al Ahly face one of the greatest challenges in their 112-year history when they try to wipe out a five-goal CAF Champions League deficit Saturday.
Mamelodi Sundowns exceeded their own expectations by thrashing the Cairo Red Devils 5-0 last weekend in the first leg of a quarter-final.
It was the heaviest loss suffered by the record eight-time Champions League winners in Africa, surpassing the 4-0 CAF Cup defeat by Enugu Rangers in Nigeria 16 years ago.
To survive, an Ahly team saturated with Egyptian internationals must become the first club to overcome a five-goal deficit in the elite African club competition.
Tanzanian club Simba SC hold the record for the greatest comeback after defeating Mufulira Wanderers 5-0 in Zambia 40 years ago having lost 4-0 at home.
History offers Ahly a glimmer of hope as they have scored seven goals once, six goals twice and five goals five times in Egypt in two-leg Champions League ties.
Former CAF champions Sundowns' worst away performance in the competition came 19 years ago when they crumbled 6-1 against Africa Sports in a group game in the Ivory Coast.
AFP Sport previews the second legs with Sundowns, TP Mazembe of the Democratic Republic of Congo, Wydad Casablanca of Morocco and trophy holders Esperance of Tunisia set to advance.
Ahly v Sundowns
Sundowns coach Pitso Mosimane has warned his team to "keep your feet on the ground and remain humble" after their greatest single-match performance in Africa.
He will hope for at least one goal from star midfielder Themba Zwane, who has already notched six in the Champions League this season.
Ahly have moved the second leg from Suez to a much bigger stadium in Alexandria, where a crowd restricted to 30 000 for security reasons will hope for a miraculous comeback.
Mazembe v Simba
Hosts Mazembe have not lost at home in the Champions League since 2009 and it is difficult to imagine Simba winning in Lubumbashi especially after being held 0-0 in Tanzania.
Rising star Jackson Muleka and veteran Tresor Mputu have spearheaded the Mazembe challenge for a sixth title, scoring four goals each in qualifying and group matches.
A Simba side coached by Belgian Patrick Aussems reached the quarter-finals despite a wretched away record, losing four of five matches and conceding five goals twice.
Wydad v Horoya
Guineans Horoya are facing a last-eight exit for the second successive season after only drawing 0-0 at home against twice champions Wydad.
Moroccan Mohamed Nahiri is a left-back, but has scored four Champions League goals while none of his Wydad team-mates managed more than one.
Horoya have struggled away to stronger sides, conceding three goals to Al Nasr in Egypt and Orlando Pirates in South Africa.
Esperance v Constantine
The outcome of this tie appears a foregone conclusion after three-time champions Esperance established a 3-2 lead away to far less experienced CS Constantine in Algeria.
A succession of 2-0 home victories eased the Tunis outfit into the quarter-finals and it is difficult to identify which players pose the biggest threat because nine have scored.
Constantine also boast many scorers but two of them, midfielder Sid Ali Lamri and striker Ismail Belkacemi, are injured and may miss the return match.