After narrow losses to Zamalek and Al Ahly in Cairo this month, the 'Harare Glamour Boys' who stunned defending champions Etoile Sahel of Tunisia in the final qualifying round are four points behind the leaders.
So maximum points on the artificial surface at the 30,000-seat Rufaro Stadium are essential for Dynamos as they try to turn the tables after a cruel blow at Al Ahly two weeks ago. Undaunted by conceding an early goal, the Zimbabweans attacked constantly in the second half and were rewarded by a Lazarus Muhoni equaliser 10 minutes from full-time.
But four minutes into stoppage time, ace Ahly midfielder Mohamed Aboutraika whipped a loose ball past goalkeeper Willard Manyatera to give the Cairo 'Red Devils' another 2-1 home triumph.
Ahly began their six-match campaign with victory by a similar score against bitter domestic rivals Zamalek, and then forced a goalless draw at ASEC Mimosas of Côte d'Ivoire on another artificial pitch.
Dynamos followed up shock home and away victories over Etoile by shading visiting ASEC 2-1 in their opening pool fixture, before falling 1-0 to Zamalek and seeing a draw they deserved snatched from their grasp by Ahly.
Zimbabwean striker Murape Murape will miss the Harare showdown due to injury, and coach David Mandigora fears midfielder Desmond Maringwa could also be sidelined for a fixture sure to attract a capacity crowd. Maringwa is the sole survivor from the team defeated 4-2 on aggregate by ASEC in the 1998 final, the best showing by a Zimbabwean club in the premier African Football Confederation club competition.
Maximum points are also essential for bottom-of-the-table ASEC on Sunday when they host second-placed Zamalek, held 0-0 at home by the Ivorians two weeks ago despite having a one-man advantage for most of the game. Midfielder Yao Kouassi was dismissed after a second caution just 18 minutes into the first half in Cairo, and an automatic one-match ban rules him out of the Abidjan encounter.
ASEC welcome back goalkeeeper Vincent Angban, defender Serges Wawa and midfielder Antoine N'Gossan, who missed the previous two rounds after being selected by Côte d'Ivoire for the Beijing Olympics football tournament.
Another club hit by suspension are Group B pacesetters Enyimba of Nigeria, who face struggling Tout Puissant Mazembe in the Democratic Republic of Congo on Sunday without star striker Stephen Worgu. The leading scorer in the Champions League this year with 12 goals received a second booking when Enyimba overcame Mazembe 2-0 in Nigeria two weeks ago, so must sit out one fixture.
After coming from behind to surprisingly hold 2007 semi-finalists Al-Hilal of Sudan 1-1 in steamy Omdurman, Cotonsport Garoua of Cameroon will hope for an even better result with home advantage when the teams meet again on Saturday.
Apart from a $1 million prize, the Champions League winners play in the annual FIFA Club World Cup in Japan in December.