Cameron Carter-Vickers will be back in the Celtic squad for Sunday’s match against Dundee United at Tannadice.
The defender missed his first match since joining on loan from Spurs in August when he sat out the 1-0 home win over Hearts.
Carl Starfelt stepped in to partner Stephen Welsh with the Swede making his first appearance in more than a month after being out with a hamstring injury.
Welsh had to be substituted last night with Ange Postecoglou likely to be assessing fitness as much as form when he gets round to selecting his side on Sunday.
Covering the post-match comments of the Celtic boss, BBC Scotland report:
“If I had to make a call Tony’s probably the one of most concern,” he said. “For him to go off it’s got to be something significant. He started the game so well.”
The Celtic boss confirmed defender Cameron Carter-Vickers – who missed the match for personal reasons – will be back for Sunday’s trip to Dundee United, while Greg Taylor is in line to return next week after a shoulder problem.
Ralston’s injury saw Josip Juranovic switch to right-back with Adam Montgomery coming on to play at left-back.
With nine more matches to be played before the January break Postecoglou will be keen to avoid more injuries as he manages his squad through a hectic and critical period.