Published Thursday, 06 September 2012
Bethany Firth celebrates her gold medal win on Friday. (© Getty)
The Team Ireland representative, who is just 16 and from Seaforde in Co Down, is understood to have aggravated an existing problem during her medal-winning swim last Friday.
Firth picked up gold in the S14 100 metre backstroke, having only been swimming competitively for three years.
The injury has already kept her out of the 200 metre freestyle heats earlier this week.
Meanwhile, Eglinton sprinter Jason Smyth remains on top form at the London 2012 Games.
The fastest Paralympian in the world won his 200m heat in a time of 21.48seconds on Thursday morning.
The Team Ireland runner is the reigning 100m/200m Paralympic champion - and world record holder for both disciplines.
He has qualified for Friday's final which starts at 7.25pm.
© UTV News