UPDATE 2-Soccer-PSG leave out Neymar again on way to shock Rennes defeat

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RENNES, France, Aug 18 (Reuters) - Rennes came from behind to stun lacklustre Paris St Germain with a deserved 2-1 victory at Roazhon Park in France's Ligue 1 on Sunday.

PSG coach Thomas Tuchel left Neymar out of his squad for the second consecutive week amid uncertainty over the forward's future and his side struggled to break down the resilient French Cup holders in the Brazilian's absence.

The visitors were gifted the opener when Edinson Cavani tapped in after a defensive mix-up, but M’Baye Niang’s strike drew Rennes level on the stroke of halftime before Romain Del Castillo headed in the winner early in the second period.

PSG captain Thiago Silva insisted that the ongoing saga around his compatriot’s future played no part in his team's poor performance.

“For everyone it's difficult, but it's not an excuse,” he told Canal Plus television channel. “Neymar was not there. We must think of ourselves. I hope it's the last (defeat of the season).”

Rennes join Lyon and Nice at the summit of the table on maximum points after the opening two rounds of the season, while the defeat leaves PSG in eighth.

The reigning French champions were frustrated by their well-drilled hosts, who have become something of a bogey team for PSG.

Sunday's victory marked Rennes' fifth Ligue 1 win against the Parisians in the last 10 years, more than any other club. They also beat the Parisians in last season's French Cup final.

“We were not attentive,” Silva conceded. “You have to raise your head, try to be better at the next game because it was not the Paris St Germain that we know.

“A physical problem? I don’t think so. We worked well. Rennes have been more solid defensively, more attentive, I do not know exactly what happened.”

The home side started brightly but they were undone on 36 minutes when Cavani pounced on a slack pass from Damien Da Silva to slot home.

Rennes, though, drew level on the brink of half time when Niang took down a cross just inside the PSG box, turned his marker and lashed a left-foot finish into the bottom corner.

The hosts then took the lead within three minutes of the restart when impressive 16-year-old midfielder Eduardo Camavinga lofted a cross into the path of Del Castillo to head home unmarked from close range.

PSG looked shell-shocked and almost went further behind when defender Jeremy Morel’s volley came back off the post.

Earlier on Sunday, Saint-Etienne were held 1-1 at home by newly-promoted Brest and Reims and Strasbourg played out a 0-0 stalemate. (Reporting by Alasdair Mackenzie; editing by Tony Lawrence )