The former TNS shot-stopper went up field and landed awkardly in his attempt to head home Ruaidhri Higgins' cross in the closing stages and although he didn't receive treatment during the final few minutes, the 28-year-old did have words with both team doctor Joe McEvoy and phyiso Colm O'Neill when he was hobbling off the pitch after the game.

"We are concerned about Gerard, it looks like he's in trouble," admitted boss Stephen Kenny.

"There isn't any ligament damage but there's a concern about possible cartilage damage, however it's too early to say how bad the injury is, he has to go for a scan this week and we'll find out for sure after that.

On the plus side both skipper Peter Hutton and Stephen Gray return to the squad for this week's trip to Bray Wanderers.

City will look to bounce back this weekend when they travel to their bogie side.

Eddie Gormley's men particularly at home have become some what of a jinx to the Brandywell out-fit.

Last season Wanderers inflicted Derry's first league defeat of the 2008 campaign in April, while in October they collected maximum points again with a hard fought 2-1 win.

Nevertheless boss Stephen Kenny wants his side to show some 'bouncebackability'.

"We have to take the good with the bad, that's our first defeat and it's a setback but we have to bounce back in the right manner against Bray this Friday, it's important how we respond," he said.

"It was a blow to lose against Sligo and we can't deny that. Our defending on the night wasn't good enough and we didn't defend well.

"However we had two absolutely certain penalties not given, which would have put us in front, both penalty claims couldn't have been anymore clear cut.

"There were no grey areas in either penalty appeal, but we didn't defend well on the night and we got punished, but that's the harsh reality of football in this league."

The Candystripes who were knocked off top spot by rivals Bohemians, after Sligo had secured a surprised 2-1 win at the Brandywell on Friday evening and the Gypsies defeated St Pat's on Saturday, but Kenny isn't really worried about moving into second spot.

"Had we have won, there would only have been seven games played so I wouldn't have been talking about winning leagues.

"Now that we've lost I'm certainly not talking about not challenging. You can only view the situation after 18 games. It's a bad defeat for us, it's one that we were capable of winning and we shot ourselves in the foot really with the mistakes at the end."