The 33-year-old playmaker, who beat off stiff competition from the Melbourne City duo of Aaron Mooy and Bruno Fornaroli to take the Johnny Warren medal, is seeking a significant pay hike to remain in the west, with other opportunities also on the horizon.
But Sage hasn’t given up hope of keeping Glory’s assist king, and attended the UEFA Champions league semi-final between Real Madrid and Manchester City with his representative to gauge how far the parties are apart in terms of reaching an agreement.
“We are talking turkey. I am in Madrid for a couple of days and we will see what we can do,” Sage said.
“We are apart on money but you never know …he hasn’t said no and I am here, so we will give it our best shot.
“Keeping him is our top priority but you can’t force people to do things. His family is a consideration also.
"He has two young kids who don’t speak English, nor does his wife, and that’s a big consideration as well.”
Sage, a Manchester City fan, made the pursuit of a Castro extension a duel mission as he watched his beloved team pipped 1-0 by Ronaldo and Co to misses out on the showpiece against Atletico Madrid.
In the wake of flurry of recent signings, including Australia representatives Chris Herd and Rhys Williams, Glory coach Kenny Lowe is due in the UK and Spain next week to look at nine players – six of whom are based in England.
“He’s going to be talking to those players with a view to making up to six signings,” Sage said.
“So, if Castro doesn’t re-sign will have somebody else to replace him from that bunch."
One of these players is Perth-born former Middlesbrough and Liverpool goalkeeper Brad Jones, whose six-month deal with Eredivisie side NEC is about to elapse.
Jones, 34, is viewed as the ideal replacement for veteran shot stopper Ante Covic who is expected to exit the club.