What a difference 11 days can make.It was just little over a week ago that Sydney FC looked to have turned things around from their dismal last season - their worst on record.They had the chance to climb to second spot on the A-League ladder with a win over Melbourne Heart on December 29 but instead suffered their worst ever home defeat - a 4-0 drubbing.On Sunday they posted their third loss on the trot, going down 1-0 to league-leading Central Coast Mariners after losing 4-2 away to Wellington on Wednesday.They now cling desperately to fifth spot, with Melbourne Victory, Adelaide and Perth hot on their heels.Sydney looked sloppy and bereft of creativity against the Mariners, despite having playmaker Nicky Carle back from injury.However, coach Vitezslav Lavicka believes the Sky Blues' main problem is mental.And if Lavicka was feeling the heat last season, things can't be much better for the Czech coach now."I think everyone is frustrated at Sydney FC at the moment including me of course," a dejected Lavicka said."Because I feel full responsibility for the team."A few days ago we had a good chance to reach second spot so everyone was confident."But in football everything changes very quickly."I think the boys are good enough physically, our main problem at the moment is up here," he said pointing to his head."We have to believe in ourselves and our confidence can pick up bit by bit."Maybe one goal, one good performance, one good win can turn things and we can start to be successful again."Skipper Terry McFlynn praised the spirit and character of the squad but admits the crisis of confidence in the team is affecting their football and their speed on the pitch.And with their next clash against reigning premiers Brisbane, things won't get any easier."We're just lacking a bit of confidence now," McFlynn said."Some players are second guessing themselves and having an extra touch, which slows things down."But confidence can hopefully be regained ... we just have to get back to work and focus on the game against Brisbane."It was the opposite story for their opponents the Mariners who are going from strength to strength, extending their unbeaten run to 12 straight games to go eight points clear atop the ladder and with a game in hand.In other clashes this round the second-placed Roar drew 1-1 to Adelaide on Saturday while the Melbourne Victory beat Newcastle 2-1.In Sunday's games Perth snatched a last minute 1-0 win over Wellington, their first ever at the Phoenix's fortes Westpac Stadium while the Gold Coast held Melbourne Heart to a 1-1 draw.