The former Great Britain scrum-half feared he had broken his thumb in the semi-final victory over Castleford, but played in the home match against Hull on Good Friday.
"He came off at Headingley and knew it wasn't right, but he tried to smokescreen it," the London coach, Dan Stains, said. "He thought he could get through on painkillers, but the X-ray shows quite a big crack at the base of his thumb and he will be out for two or three months.
"It's a blow for him and we will miss his organisational skills, but these things sometimes happen for a purpose."
Edwards, 10 times a Wembley finalist, is replaced today by Glen Air, the Australian half-back who was in and out of the team last year and has just made a timely recovery from a pre-season knee injury.
"It's a great opportunity for him," Stains said. "Glen's got my full support and I know he will do a good job. From what I've seen, he's got the talent and we will find out what he's made of over the next month."
Stains also has problems in his pack for today's return to Headingley, with Robbie Simpson, Robbie Beazley and Peter Gill all doubtful. In traditional manner, he will try to isolate the match from events a month ahead and concentrate on maintaining the Broncos' winning start in Super League.
"Our focus is on the here-and-now and it's the two competition points we need," he said.
At least one of Super League's other perfect records will disappear today when Bradford go to St Helens. Both have had morale-boosting victories over their traditional rivals - the Bulls over Leeds and Saints at Wigan - in the first part of the holiday programme, but Bradford have had an extra day to recover.
The other perfect record, surprisingly perhaps, belongs to Warrington, who host Gateshead, themselves encouraged by their first competition points against Wakefield on Good Friday.
Wigan go to Wakefield with two more players out of action. Danny Moore and Mark Reber's injuries in the defeat by St Helens force their coach, John Monie, to reshuffle what look like suspiciously limited resources, with Lee Gilmour at centre and Jason Robinson back in his old schoolboy position of scrum-half.
Dwayne West should get his first start on the wing, despite an uncomfortable debut against St Helens, and Denis Betts makes his first appearance of the season.
The televised game at noon sees Sheffield try to maintain the momentum from their first victory against Huddersfield at Hull, one of three teams without a win so far.
The broader question is how clubs will cope with games on either side of the weekend and whether the high standard of rugby in the early stages of the season can be sustained.
Taking the Cup semi-finals into account, there can rarely have been a better week of big games than the one just ended. The quality of rugby has shown what it is that Super League could put at jeopardy by trying to overload the number of fixtures.Reuse content