The Champions League has reached a crucial stage

The season's giantkillers are APR of Rwanda and they have received a timely boost ahead of their home leg against Africa Sports of Ivory Coast.

The Kigali-based military club won East and Central Africa's Cecafa club championship last week when they came from behind at home to defeat Ulinzi Stars of Kenya 3-1 in the final.

APR's success comes on the back of Rwanda's first ever appearance at the African Cup of Nations earlier this year in Tunisia.

Last year APR were the surprise side in the Cup Winners Cup by reaching the semi-finals and this year they have set the Champions League alight with a series of impressive victories.

In the preliminary round their win over Anseba of Eritrea was not surprising but the result was an eye-opener with APR winning 7-1 at home and 4-2 away.

Next up was much more formidable opposition in the form of Zamalek, champions of Africa a record five times and packed with Egyptian stars well versed in the rigours of international football.

The Rwandans led in Cairo before losing out narrowly 3-2 and then at home caused a major shock with three goals in 15 minutes en route to a stunning 4-1 triumph.

The victory was sealed by a Jimmy Mulisa goal 10 minutes from full-time.

Jimmy Mulisa is a key figure for Rwandan side APR

APR's coach Lt. Jean Marie Ntagwabira doesn't seem worried about his opposition.

"My players have worked hard and they have an excellent attitude and Africa Sports should be very careful when they enter the our Amahoro Stadium this weekend," he told BBC Sport.

He has a full squad of players to chose from that includes Olivier Karekezi, who was top scorer at the Cecafa club championship, as well as Jimmy Gatete and Mulisa.

APR also has several imported players including Mark Sirengo from Kenya, Hamdun Makombe Makoye from Tanzania as well as three Ugandans Manfred Kizito, James Odoch and Francis Gonzaga.

Africa Sports however will be no pushover as a 5-1 first round victory over Douanes of Togo illustrates their strength with the Abidjan Eagles winning both legs of the West African showdown.

Runners-up to Zamalek in the 1986 Champions League final, Africa Sports have a proud pedigree, reaching four Cup Winners Cup finals and winning two, plus the African Super Cup once.

Al-Hilal of Sudan are another club who defied the odds in the first round, shocking three-time champions Al-Ahly 1-0 in Egypt through an early Richard Gastin goal and drawing 0-0 at home.

South African opponents SuperSport United host the first leg and enter an intriguing showdown fresh from a 3-0 hammering of leaders Kaizer Chiefs in the national championship with Swazi Dennis Masina scoring a superb goal.

Enyimba of Nigeria, who last year became the first champions from Nigeria, entertain Angolan outfit Petro Atletico in the south-east town of Aba and should be capable of building a tie-clinching lead.

Nigeria's Enyimba are without their coach Michael Urukalo

The Nigerians however will have be without their Australian coach Michael Urukalo, who is in Australia to attend to a 'family medical emergency.'

"It's sad I have to go and attend to a family emergency, it's unfortunate but I will miss this weekend's champions league game in Aba" he told BBC Sports.

"I presume Enyimba will understand my situation, my heart will be with the team this weekend.

"We have a bunch of fighters in the team and am sure my absence will not be felt on Sunday" he added.

Orlando Pirates, the only South African side to conquer Africa, entertain Bakili Bullets, the Malawian team bankrolled by president Bakili Muluzi, who has vowed to make them a force on the continent.

Esperance of Tunisia, whose victory over Zamalek in the 1994 decider has been followed by a series of disappointing campaigns, have hired Luis Oscar Fullone, the Argentine coach with two Champions League titles to his credit.

While the Blood and Gold brushed aside minnows Sahel of Niger last month, Cotonsport Garoua of Cameroon should prove much harder rivals having reached the Caf Cup final last year.

The other Tunisian contenders, former Cup Winners Cup, Caf Cup and Super Cup winners Etoile Sahel, are away to Hearts of Oak, the Ghanaian club who shocked Esperance in the 2000 final.

Canon Yaounde of Cameroon, three times champions but a bitter disappointment last year in the group phase, visit Jeanne d'Arc of Senegal, shock conquerors of Moroccans Raja Casablanca in the previous round via a penalty shootout.

And USMA of Algeria, who suffered the heartbreak of a stoppage-time loss to Enyimba in the last semi-finals, host Asante Kotoko of Ghana, who ousted Asec Abidjan of Ivory Coast in a high-profile first round tie.