Sydney FC are set to announce their fifth coach in as many A-League seasons after cementing their ruthless reputation by sacking John Kosmina with a year remaining on his contract.After Sydney's worst-ever season, in which they failed to make the finals for the first time, Kosmina on Saturday followed former coaches Terry Butcher and Branko Culina on to the scrap heap of the A-League's so-called "glamour club".In typical Sydney FC-style, it is believed the club has already lined up a replacement, who they will officially announce within the next few days.Rumoured replacements include Czech former Zenit St Petersburg coach Vlastimil Petrzela, the club's now assistant and recently-retired captain Tony Popovic and even Manchester United legend Roy Keane.Kosmina's position was the subject of heavy speculation with the club about to come under the control of new owners, but he had been recently promised his position was safe.That assurance proved futile on Saturday when the club released a brief statement claiming they and Kosmina had "mutually agreed" to a contract termination immediately."Sydney FC would like to thank John for his contribution to the club over the last 15 months, said Sydney FC chief executive Stefan Kamasz."We would like to wish John all the best in his future endeavours."Club captain Steve Corica, who did not know of the sacking until contacted by AAP, admitted he was not overly surprised with the decision."It's a bit of a shock but there was a lot of talk about whether he was going to stay or go so obviously the club's decided for him to go, that's football," Corica said."It was our worst season in four years ... the other coaches got the sack even by making the top four, so obviously the club thought that was the best thing for the club."Sydney finished fifth this season, two points outside the top four, after winning just seven of their 21 games.It was highly disappointing for the pre-season favourites who had been bolstered with recruits including John Aloisi, Mark Bridge, Simon Colosimo and Stuart Musialik.It is believed Kosmina's reported rift with $1.4 million marquee striker Aloisi, who had a dismal season himself, may have played a role in his sacking.Russian businessman David Trakovenko and his son-in-law Scott Barlow will officially take over the club in March, but it is also understood sections of both the old and new factions wanted Kosmina sacked.The new coach will step into one of Australian sport's hottest seats.Sydney have strived to match the success achieved under Pierre Littbarski, who led the club to the inaugural A-League title but quit for a bigger pay packet after that first season.Since then Butcher, Culina and now Kosmina have all been axed for not producing instant results, creating the most unstable of footballing environments."We've had four coaches in four years, so we've gotten used to this," said Corica, who is undecided if he will play on next year or retire."I think it's got to be the right person as well, so I hope they bring in the right coach and they do get the stability that the club needs."It's something we can look forward to a new coach coming in and we go from there."Kosmina was unveiled as Sydney coach after Culina was sacked in October, 2007, and enjoyed a positive start to his tenure, leading the side to the 2007/08 finals, where they were knocked out by Queensland Roar.The former Adelaide boss finished his stint at Sydney with an A-League win-draw-loss record of 13-11-11.Kosmina was the inaugural manager of Adelaide United, leading them to the A-League grand final in 2006/07 season before being beaten by Melbourne 6-0.A colourful figure, Kosmina has been involved in several controversies including a memorable sideline scuffle with Victory captain Kevin Muscat in the grand final loss and a similar incident involving Danny Allsopp this season.