Blanc's men host Saint-Etienne at the Parc des Princes having not beaten Christophe Galtier's side in any of their last three league meetings.
The defending Ligue 1 champions are eight points clear of Monaco at the top of the table and edging closer to retaining the crown.
PSG are likely to face a stern test against Saint-Etienne, who are four points adrift of third-placed Lille in the race for the final UEFA Champions League spot.
Verratti missed Wednesday's 2-1 Champions League last 16 win over Bayer Leverkusen with a knock, but the Italian could be in line to make a comeback this weekend.
However, Gregory van der Wiel remains on the sidelines with a knee injury that kept him out of the second leg with Leverkusen.
"Gregory is in Munich for treatment," Blanc said. "He is already out for this match against Saint-Etienne.
"Marco is much better. We will wait for the workout on Saturday to see if he is fit to play Sunday."
PSG appear to have all but secured the French title for a second consecutive season, but Blanc insists that his side cannot afford to let standards drop in the final 10 league games of the campaign.
"It (motivation) is always there, for every game," Blanc added. "There is always a risk of losing concentration and this is the case in all clubs.
"This is not the time to relax, and I think the players are aware of that."
