Yanco-Wamoon look to be without their leader for an extended period of time after he was hurt late in his sides 36-16 loss against the Waratah Tigers on Sunday.
Dumbrell went for a darting run and suffered a dislocated ankle and will have surgery on either Monday or Tuesday to fix the fracture in his ankle.
Waratahs led 36-16 when the injury occurred on a hot day at the Exies Oval.
The match was much closer than the end scoreline indicated as the two sides went try for try in the opening stages.
By midway through the first half, Yanco-Wamoon led 16-12 after the lead had changed five times.
The Waratahs then bucked the trend and scored the final two tries of the half – through Kose Lelei and Michael Kilby – to take a 24-16 lead into half-time.
Mistakes crept into both side’s games when the second half commenced but the defensive efforts also strengthened.
There was minimal attacking opportunities in the opening 15 minutes of the first half before Adam Twigg scooted from dummy half close to the line and crossed for his third try of the day.
More mistakes followed the try as the Waratahs knocked on when working the ball out of their own half from the kick-off.
The following three sets saw three more mistakes made – two from the Hawks and one from the Waratahs.
The Griffith outfit then made the most of the possession when Shorne Ngu steamed onto a short ball to hand the Waratahs a 20-point lead with 20 minutes to go.
Six minutes later, Dumbrell was injured in the Waratahs’ half before the match was called off early.
At that stage according to club president Craig Higgins it looked like the side were getting back into the game but admitted the side were probably their own worst enemy.
“We dropped a lot of ball,” he said.
“The game wasn’t going our way and we were making a lot of errors.
“We decided after Glenn went down that we probably weren’t going to get back into the game so it was called off with about 15 minutes to go.”
Before picking up the injury Dumbrell picked up a double while Troy Preston scored the other Hawks’ try.
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