Damien Balisson completed a sweeping counterattack with a sweetly-struck 16th-minute winner on the second day of group play in the annual southern Africa championship.
Brazilian Filho, a greying 77-year-old with a constant shy smile, interpreted for Ronaldo when the Portuguese moved to Old Trafford 15 years ago.
Filho was a youth coach at Manchester United, working with managerial legend Alex Ferguson when the club dominated English football.
He later retired only to be persuaded to take over struggling Mauritius, who are ranked 161 in the world, 42 places below Malawi.
A mixture of disciplined defending by Mauritius and a couple of woeful close-range misses from Malawi in northern city Polokwane contributed to the unexpected outcome.
Earlier, Botswana took a fifth-minute lead from a penalty en route to a 2-1 victory over three-time champions Angola in the first match of a double-header.
Kabelo Seakanyeng converted the spot kick after he was fouled by the Angolan goalkeeper, who had to pick the ball out of the net again in the final minute of the opening half.
A brilliant pass picked out Onkabetse Makgantai and he darted through the middle before lobbing the ball into the net.
Joao ‘Caporal’ Manha cut the deficit on 58 minutes, but Botswana held on for a win that put them top of the table on goals scored from Mauritius.
On Tuesday, the second round of Group A fixtures will be held with Comoros facing Mozambique followed by leaders Madagascar against the Seychelles.
The two group winners will join defending champions Zimbabwe, Lesotho, Namibia, South Africa, Swaziland and Zambia in the quarter-finals this weekend. DM
