Both sides were victorious in their Group C openers a fortnight ago, and meet at the Parc des Princes where the winner would move to the head of the table.
Despite the Portuguese club's mixed start to their domestic campaign, Blanc feels that PSG cannot take Benfica lightly.
"We know Benfica are fifth in their league, but it would be a safe bet to say they will finish in the top two or three come the end of the season," Blanc said in his press conference. "They have been very consistent, which explains their great experience in the Champions League. We have to respect them, but must also have the will to win and cause them a lot of difficulties.
"In the league they like to dominate possession and dictate the game, but I don't know if that is the way they plan to play in the Champions League and, what is more, away from home in Paris. That will be our objective, though. Whoever manages to dominate possession will control the game.
"We know Benfica well, even more so since we've scouted them a few times since the draw. I know Jorge Jesus – we had an opportunity to talk at the recent [UEFA elite club] coaches forum. It is their intention which will shape the game – will they sit deep and wait at the beginning of the match, or try and attack straight away? I have no idea."
The match kicks off at 7.45pm.