Zlatan Ibrahimovic's hotly-contested second-half goal gave holders Paris Saint Germain a place in the last four of the League Cup after a 1-0 win over St Etienne on Tuesday.

Ibrahimovic's 72nd minute goal, which he chested over the line despite the efforts of goalkeeper Stephane Ruffier to claw it away, was disputed both by the home players and the spectators.

Angry fans hurled projectiles on to the pitch, including a plastic water bottle thrown at a linesman, and St Etienne coach Christophe Galtier urged the crowd to calm down.

The match was held up for around 10 minutes while order was restored.

The victory, though, is welcome both for PSG and especially for the coach Laurent Blanc, who has come under pressure in the past four weeks after a series of disappointing results and player trouble.

PSG came into the game on the back of a 4-2 league defeat by modest Bastia last Saturday, with Blanc having disciplined big name players Edinson Cavani and Ezequiel Lavezzi for returning late from holiday.

Blanc, who has guided PSG into the Champions League last 16 where they will play Chelsea, said that he had not been very confident before the match after what he had seen against Bastia.

"After the Bastia match I had the impression that we no longer knew how to play and there was a bad atmosphere within the squad," said Blanc.

"Tonight, though, I saw positive things and we have won at a place where it is difficult to do so.

"However, I am neither more reassured than I was before the match, but on the other hand neither am I very worried."

Earlier, Bastia continued their good run of form, recovering from going a goal behind early on to storm into their first League Cup semi-final since 2000 with a 3-1 victory over Rennes.

The Corsican side, who unusually for a top tier side in Europe these days, fielded six homegrown players in their starting line-up and another five on the bench, were helped considerably by their opponents having two men sent off.

Former France international striker Djibril Cisse rounded off a joyous night for Bastia as the 33-year-old fired home a powerful shot a minute from time.

"I am happy for the players for all the work they have put in in recent weeks," said Bastia coach Ghislain Printant, who is bidding to become only the second coach in the club's history to land a trophy with their sole piece of silverware coming in the 1981 French Cup.

"This semi-final is a deserved reward for them."

The semi-final line-up will be finalised on Wednesday when Monaco host French Cup holders Guingamp and Lille are at home to Nantes.