Former Socceroo Robbie Slater feels the time has come for Sydney FC's marquee man Brett Emerton to show the elusive form Sky Blue fans have been craving.After slumping to their worst ever finish last season, a lowly ninth on the ladder, Sydney desperately hoped the injection of former Blackburn Rovers skipper Emerton - the first ever player to exchange the English Premier League for the A-League - would help change their fortunes.And while the Sky Blues have shown more promise this season to sit in fourth spot within reach of league-leaders Central Coast, they suffered their worst ever home defeat on Thursday - a 4-0 drubbing at the hands of Melbourne Heart - in Emerton's first match as captain.To make matters worse 16,007 people - the club's biggest home crowd since their major semi-final against Melbourne Victory in March 2010 - were there to witness it.Slater, who also made the move from England to play in Sydney in 1998, admits it does take time to adjust to life back at home but says Emerton now needs to show the tough Sydney fans what he's made of."I think it's got to happen sooner rather than later," Slater told AAP on Sunday."Especially with Emo because Sydney's a hard market but the whole league needs a successful Sydney."The fans are very tough here and they're very harsh."But in terms of how much time we give players like Emo and Harry (Kewell) to find their form I think the time is about now."We're sort of half-way through the season and I have no doubt that both of them will have very good second halves."Melbourne Victory's Kewell has admitted the high standard of the A-League proved a "rude awakening".But while he managed to get a monkey off his back and score his first goal in open play for his new club it still wasn't enough to save them from a 3-1 loss to Brisbane on Saturday.Emerton has so far failed to have any real impact on the field."For both Brett and Harry they probably haven't had the impact that everyone's been waiting for," Slater said."But I think that's just them adapting to life back in this country and to a league that they probably didn't think was going to be this tough."But the punters just want to see Emo play and play well and I think it's going to come."Slater feels a key reason Emerton hasn't fired is his continual shifting between positions as coach Vitezslav Lavicka seeks to accommodate injuries and suspensions."But I think there is going to come a point when Vitezslav Lavicka has to make a decision with Emerton where to play him and to play him in the same position all the time," Slater said."My personal opinion is he's much better on the right hand side even a right fullback."You can understand Lavicka needing to do what's best for the team, but I think it's time to maybe think about what's best for Brett Emerton."