The recuperating Ghanaian completed an eighteen-month loan switch from English giants Chelsea, but fitness issues have prolonged his anticipated second debut.
He was on the books of the Royal Blues last season – on loan – before picking up the problematic long-term injury while playing for Ghana at the 2017 Africa Cup of Nations tournament in January.
“Baba Rahman needs time but he’s working extremely hard,” Schalke manager Domenico Tedesco told pressmen.
“We need to have him at 100 per cent before he can be in the matchday squad.”
Baba joined Chelsea in August 2015 but limited opportunities at Stamford Bridge warranted a move to Schalke a year later after playing 15 league games in his first season with the Blues.
The switch to the Bundesliga was, however, cut short by the injury.
He made 13 league appearances, involving seven starts, before the incident.
Originally scheduled to return to action after seven months, a series of complications kept him out of action until last month when he made a second half outing for Chelsea’s reserves in a fixture with Queens Park Rangers.