Bulldogs playmaker Matt Burton is set for scans after a hamstring issue that could cost him a trip to Las Vegas.
The potential withdrawal looms with only five days before the team is scheduled to fly overseas.
Burton grabbed at his left leg and required sideline treatment at McDonald Jones Stadium during Saturday's trial match against Newcastle.
He was forced off in the first half and did not return to the field.
Canterbury went on to secure a 28-0 victory in the match.
Off-season signing Sean O'Sullivan moved into the five-eighth role after Burton's departure.
The club is also without rookie playmaker Mitch Woods, who is already out with a separate hamstring injury.
That absence increases pressure on the coaching staff to manage their remaining playmakers carefully.
Coach Cameron Ciraldo must now weigh the risks of including Burton on a long-haul flight to the United States.
The hope would be that Burton recovers in time for the March 1 season opener against St George Illawarra.
A final decision on his travel and match readiness is expected after the results of the scans.