The visitors started the evening in blistering fashion, taking the lead in the second minute through French international forward Andre-Pierre Gignac.
Marseille's blitzkrieg start to the match showed no signs of letting up, with the visitors doubling their advantage just three minutes later as Dimitri Payet capitalised on poor defending from the hosts.
Payet helped himself to his second with 16 minutes on the clock, finding the back of the net from close range after Mathieu Valbuena's drive was spilled by Samassa.
Guingamp defended poorly for much of the game, but did create a few chances of their own, and had a golden opportunity to reduce the deficit early in the second half when they were awarded a penalty.
Souleymane Diawara was penalised for a late challenge in the box, and Mustapha Yatabare was the man tasked with putting away the spotkick, but visiting keeper Steve Mandanda guessed right and palmed it away.
The home side were much improved in the second period, and did pull one back in the 75th minute through Yatabare, who turned in Reynald Lemaitre's pass following some scrappy Marseille defending.
However, this proved to be little more than consolation as Marseille held on comfortably for the win.