Following a testing week in which PSG were beaten by Dijon and then saw coach Thomas Tuchel linked with Bayern Munich, Icardi’s eighth goal in nine games for the club secured their progress.
Swift advancement comes as a boost to Tuchel, who insists his future lies in Paris, but this was far from a vintage performance.
The Ligue 1 champions have four wins from four in the competition this season, while they are still to concede, yet both records would have been tarnished had Keylor Navas not saved Mbaye Diagne’s penalty in a particularly poor second half.
PSG scored inside seven minutes en route to a 5-0 win in Belgium a fortnight earlier but laboured early on this time around until a fortuitous bounce fell Icardi’s way midway through the first half.
The on-loan striker had been a peripheral figure to that point, yet he could hardly have missed as Colin Dagba’s low cross deflected through Simon Deli’s legs for a simple tap-in.
The hosts still were not entirely convincing and would have been pegged back on 50 minutes but for Navas’ reactions.
The goalkeeper scrambled to keep out an Emmanuel Bonaventure Dennis effort that struck David Okereke and span towards goal, before bouncing to his feet to deny the latter again on the rebound.
Dagba struck the outside of the post as he sought to force in a strike from an improbable angle in a swift PSG riposte, but Tuchel’s side stalled again and were once more grateful to Navas.
Thiago Silva was punished for a clumsy challenge on substitute Diagne, who took the spot-kick himself but sent a tame effort straight into the hands of the keeper.