The likes of Nikita Rukavytsya, Brendan Hamill, Anthony Golec, Jason Trifiro and Yianni Perkatis are also among those whose deals will expire at the end of the Wanderers' Asian Champions League campaign.
Covic, who turns 40 in June, has not been able regain the blistering form that saw him awarded player of the ACL tournament last year.
He has been replaced by Dean Bouzanis between the sticks on several occasions this season including in the Wanderers' 1-1 draw with Melbourne City on Friday, with the 24-year-old no doubt eyeing the No.1 spot.
Juric meanwhile, turned down a big money offer from China in January to stay at the Wanderers and seems to be short on any other offers since.
With just three A-League games remaining and the Wanderers yet to secure their progression to the ACL knock-out phase, time is running out for the players to prove their worth.
Popovic says there's no lack of motivation in the dressing room but admits everyone is being assessed.
"All players at this club are trying to prove themselves every day whether their contract's up or not," he said on Monday.
"I'd be disappointed if only players who are looking for a contract next year are doing a little bit more.
"Nikolai (Topor-Stanley) has got a contract for a few more years and he was limping the whole game against Melbourne City and didn't want to come off.
"So there's no one at this club who doesn't put in every day but of course we're assessing everyone in terms of for next year."
