FC Porto stars were reduced to tears after a horrific incident marred their league clash against the side of South African duo Sphephelo Sithole and Thibang Phete, Belenenses.
Porto were aiming to close the gap against league leaders Sporting Lisbon on Thursday evening but dropping two points against Petit's side would have been the last thing that crossed their minds.
Scroll through the gallery to see the images of the horror incident during the LigaNos clash
In what should have been an exciting moment for South African talents Sphephelo Sithole (21) and Thibang Phete (26) who starred in central midfield over the full 90 minutes, the fixture will be remembered for unsavoury scenes.
Guinea-Bissau international defender Nanu collided with opposition goalkeeper Stanislav Kritsyuk before landing on his head with players immediately showing distress alongside him as the emergency ambulance rushed on to the pitch.
Porto soon confirmed that he had suffered a 'cerebral concussion and spinal cord injury with loss of memory' which left him unaware and seemingly unconscious on the pitch.
"I wish our team-mate Nanu a speedy recovery," former Real Madrid defender Pepe said after the game as he was reduced to tears. "The doctors in the ambulance told me that he was doing well, that he was already conscious."
Porto remained second in the Portuguese top-flight while Belenenses dropped into 12th place in the 18-team division.