After leaving ANZ Stadium in a moonboot and strapping, he will undergo scans on Monday and it’s feared he has suffered a fractured ankle and hamstring strain.
Skipper Greg Inglis is a chance to return from a shoulder injury next week while Jacob Gagan and Mawene Hiroti are other options.
The Rabbitohs remain one of only two undefeated sides after three rounds — along with Melbourne — after Cody Walker inspired them to a patchy victory.
Walker had a hand in three of his side’s four tries, including Campbell Graham’s double.
Despite sitting in second, coach Wayne Bennett refused to be pleased with his side, describing their effort as «mixed»
«To say I’ll be happy about something, that’ll be an overstatement,» Bennett said.
«We got the job done, I was pleased about that. They’re a difficult team to play.
«I’m not jumping out of my skin but I’m realistic enough to know to win three games out of three isn’t a bad effort.»
After leading 18-8 at halftime, the home side opened up a 24-8 advantage, only for the Titans to come storming back into the contest with two tries in six minutes.
Despite being winless and scoring just six points in the opening fortnight and without key trio Ash Taylor, Tyrone Roberts and Nathan Peats, Garth Brennan’s side showed plenty of heart.
They set up a grandstand finish when Don scored his 68th four-pointer for the club, surpassing David Mead as the Titans’ greatest try scorer.
Gold Coast looked like they had bombed a try when Kelly flung the ball in-field to Souths’ Ethan Lowe, only for Don to come up with a one-on-one steal to make it 24-20 with 13 minutes remaining.
However, two Adam Reynolds penalty goals sealed the result.
The Titans were crippled by their own ill-discipline, losing the penalty count 9-1, however coach Brennan couldn’t find reason to complain about the officiating.
«We need to be better. There was a leg pull, hand on the ball, offside by a metre. They’re penalties — I can’t argue about them,» Brennan said.
«Were they squeaky clean? I don’t know. But I can’t criticise the referees on the penalties against us. As far as I could tell they were warranted.»