Alan Curtis fumes at refereeing in Swansea's loss to Sunderland

Alan Curtis was left to bemoan what be believed to be a series of refereeing errors as Swansea lost 4-2 at home to fellow relegation strugglers Sunderland.

The interim Swans boss argued that two of Jermain Defoe's three goals in the Premier League clash at the Liberty Stadium on Wednesday night were offside and felt that Kyle Naughton won the ball in the tackle that saw him shown a straight red card before half-time.

The hosts were 'fortunate' to be awarded a penalty in the first half, Curtis admitted, and claimed the decision was indicative of referee Graham Scott's performance as a whole.

"There was a penalty decision given to us which, looking at it again, I don't think it was a penalty and I think that summed up the referee's game," he said.

"All the major incidents in the game I thought he got totally wrong."

While unhappy with numerous decisions by the officials, it was the sending off of Naughton that most irked Curtis.

"I thought the first and the third goals, the third especially, [were offside]," he added.

"Again, when you look back, they are clearly offside but I think the biggest one for us was the sending off.

Live Ford Monday Night Football

"We were a bit fortunate with the penalty decision, but when you go down to 10 men - I think we played probably close to an hour with 10 men - that's the one that really sort of killed us and affected us more than anything.

"I thought at the time it was a really harsh decision and when you look at it again, he clearly wins the ball and it's another major decision that the referee got wrong."