The Croatian defender has been a free agent since leaving Parkhead last summer and while he was linked with a number of potential new clubs including AC Milan and Trabzonspor in Turkey, he remains without a club.
Southampton are understood to be weighing up a move to bolster their defensive options, having conceded 18 goals in their last five league games including nine against Manchester United.
While Jannik Vestergaard and Mohammed Salisu have returned from injury, with the latter still to make an appearance since his arrival last summer from Real Valladolid, reports suggest Ralph Hasenhuttl could still look to bring in the 26-year-old.
Injury concerns
Simunovic was released by Celtic after five years in which he playe 129 times but succumbed to a number of injuries. He suffered an ankle injury shortly after signing in September 2015, and sustained knee ligament damage four months later.
In September 2019 the former Dinamo Zagreb youngster suffered another knee injury, playing just 13 times in all competitions that season.
Where to next?
Augsburg, who currently lie in 13th place five points off the relegation play-off places, have conceded 11 goals in their last six games – four of them to tenth-placed Stuttgart – while Pellegrino Matarazzo’s side have let in 16.
Simunovic is understood to be open to moving to either England or Germany, having previously agreed to join Italian side Torino during his time with the Hoops only for the deal to be cancelled after the clubs failed to agree a fee for the centre-back.