Blanc's men have already qualified for the last 16 and secured top spot in Group C.
The former France coach intends to rotate his squad and blood young players at Estadio da Luz on Tuesday, but is hopeful his revamped side can stand up to the test and become the first French team to taste victory at the venue.
"There will be players who will find some game time - it's good for them," Blanc said.
"No French team has won here; this is a great challenge for us."
PSG eased to a 3-0 win over the Lisbon club at the Parc Des Princes in October, and Blanc is determined to preserve an unbeaten group-stage record.
"It's rare to play such a match with no pressure to win, because we are already qualified and top in the group," Blanc added.
"For the young players it is amazing to have such a game, in a magnificent stadium - a place steeped in history, without any pressure.
"But we will not play with youth only, there will be international power.
"Let me be clear: we do not come here to make up the numbers, but to be competitive.
"We know it will be difficult, but we come here to win."
