Thiago Silva nods holders PSG into last four

Also into the last four are Nancy, Monaco and Bordeaux, who won their quarter-final 3-2 at home to Guingamp earlier in the evening.

Home side PSG were all over Metz, struggling near the bottom of Ligue 1, from the off and should have been 2-0 ahead after a quarter of an hour.

Both times it was striker Cavani who was wasteful, heading wide from near the penalty spot and then minutes later seeing his shot from point-blank range saved by the legs of goalkeeper David Oberhauser.

Angel Di Maria -- who has failed to really win over the fans at the Parc des Princes since his big-money move from Manchester United -- was the next one guilty of profligacy, attempting to set up Cavani with a panenka-style pass when a simple cross would have sufficed.

The pressure finally told shortly before the half-hour mark when Brazilian defender Silva, a doubt coming into the quarter-final, rose to thump home a header from a Di Maria corner.

Metz offered nothing as an attacking force and had just one shot on goal -- a tame free kick that was easily saved -- in the first half.

The second half was more of the same. Cavani missed another easy header, this time from a Di Maria clipped cross, on 50 minutes and a minute later the increasingly influential Argentine winger Di Maria had an effort cleared off the line.

Di Maria was heavily involved again after the hour, his run ending up with Cavani -- the top scorer in French Ligue 1 -- having yet another chance saved.

On 72 minutes the hosts finally sealed the game with their second -- and it was Silva again with the header, this time from a bending Di Maria set piece. 

There was still time for Uruguayan striker Cavani to miss when he should have scored, volleying over from another Di Maria cross on 78 minutes.

PSG coach Unai Emery subbed the 29-year-old Cavani two minutes later.