Rangers defender Nikola Katic is set to miss the start of the season after suffering an injury in training.
The Croatia cap is out for "the foreseeable future" having sustained the damage more than a week ago, according to the Ibrox club.
Rangers open their Scottish Premiership campaign away to Aberdeen on 1 August.
And Steven Gerrard's side will attempt to overturn a 3-1 first-leg deficit in their Europa League last-16 tie against Bayer Leverkusen on 5 or 6 August.
Katic, 23, has played 59 times in his two seasons with Rangers, and last term the centre-back extended his contract until 2023.