Sydney FC have a fight on their hands to keep Milos Ninkovic beyond the end of the A-League season, with manager Steve Corica vowing to do everything in his power.

The 34-year-old is weighing up an offer from new A-League franchise Macarthur for next season on an extended deal, with a decision to be made next week.

Speaking ahead of Saturday's A-League clash with Central Coast at Netstrata Jubilee Stadium, Corica revealed he is unsure of which way his star midfielder is leaning.

"We're obviously doing our best to keep him because he's one of the legends of the club and we want to keep him for another couple of years, hopefully, or however long he can play for," Corica said.

"I think next week will be a busy week with Ninko, we want to get the game over and done with this week. He wants to concentrate on what he does best, which is play football."

The ladder-leaders face a difficult task of juggling the salary cap to ensure they can re-sign as many players as possible, but Corica is hopeful of presenting a deal Ninkovic can't refuse.

"We have to, otherwise he'll probably go," he said.

"We're doing our best. We have a salary cap, we have a budget and we have to try and fit everyone into that.

"We still have other players to re-sign as well who are key players for us, as well as Ninko.

"It's juggling and trying to get everyone because we really want to keep all the players we can from this year."

Losing Ninkovic would be a bitter blow for the Sky Blues leading into the 2020 Asian Champions League having drawn the South Korean and Japanese champions in their pool.

Should he leave the club, Ninkovic would still be eligible for selection for the group stages before joining Macarthur for the A-League pre-season in July.

However, Corica is adamant the high-profile contract negotiations have not been a distraction for Ninkovic or the team, who are five points clear on top of the ladder heading into round 10.

Sydney FC are coming off a 5-1 thumping of Brisbane Roar and have won all of their past five games.

The bottom-placed Mariners have won just two games this season and have a horror record to overcome, beating Sydney FC just once in the past five seasons.

***STATS THAT MATTER

- Central Coast have accrued only one win against Sydney FC across the past five A-League seasons - a 2-0 win at Central Coast Stadium in November, 2017.

- Sydney FC have won nine of their past 10 A-League games, including their past five on the bounce across which they've scored 16 goals.

- Sydney FC keeper Andrew Redmayne has a 70 per cent save rate this season, the highest of any goalkeeper.