Guimaraes looked imperious from the start and they should have taken an early lead when Andre Andre headed a corner onto the crossbar in the eighth minute.
Hosts Belenenses received a boost to their chances in the 21st minute as Nii Plange received a straight red card for a strong tackle on Miguel Rosa.
Their second arrived 12 minutes later, with Tomane guiding a glancing header past Jones after an inch-perfect cross from Hernani.
The visitors wrapped up the win just before the hour mark as Jones inexplicably palmed Alex's free-kick into his own goal, although it was the Guimaraes man's name that was added to the scoresheet.
Victory saw Rui Vitoria's men make it three wins from three matches to go top of the fledgling table - at least for the time being.
Sergio Conceicao continued his unbeaten start to life as Braga coach with a 2-1 triumph over Estoril - a match that will be remembered for a trio of memorable strikes.
Visitors Estoril, who have been drawn alongside PSV Eindhoven, Dinamo Moscow and Panathinaikos in this season's UEFA Europa League, have not started the season well.
Pedro Santos put Braga ahead in the 34th minute with a moment of brilliance, as he cut in from the right and blasted an unstoppable effort into the top-left corner of the net.
