It is certainly a concern, not least because Ireland then have to face, and beat, Switzerland the following Wednesday to reach, in all probability, the play-offs. It gives little time for Duff's wound to heal. Wild horses, however, would not prevent Duff from playing Cyprus. The 26-year-old winger's devotion to the cause is unquestionable. Indeed, he has hampered his club career in the past, attempting to put off a shoulder operation last year, to turn out for his country.
How Kerr, in the absence of Roy Keane and other key players, needs a big performance from Duffer at the GSP Stadium in Nicosia. Anything short of victory is unthinkable and Duff is the player most likely to provide the route to that.
Creating chances, rather than scoring them, with just seven goals for Ireland in 58 appearances, is his stock in trade but his absence would severely deflate the nation's hopes and morale at a time of great sensitivity. Kerr is dangling at present, his up-for-renewal contract not even a subject for discussion, with a noose about to be tightened around his neck before he celebrates his third anniversary in charge. His pre-match press conference, scheduled for early this morning, should be a study in body language if nothing else.
Kerr did not speak yesterday. Indeed, the sum total of his utterances to the media since the Irish squad assembled on Tuesday morning has been timed at just 63 seconds which, never mind the pressure on him, is pretty poor for the manager of a national team in a World Cup week.
Instead, in the 30C heat (thank goodness tomorrow is an evening kick-off) there was the straightforward assessment of the ever-honest defender Andy O'Brien. "However the group pans out is beyond our control," the Portsmouth man admitted. "We are just concentrating on ourselves."
He touched on the future of Kerr, not known to be a fan of O'Brien's and more likely to favour Richard Dunne tomorrow, by saying: "Football is about opinion from the top to the bottom. As a player you have a duty to do your best and we are just concerned with doing our jobs. The situation is nothing to do with the players. The powers that be will decide that."
Those powers, the Football Association of Ireland, certainly lie in wait even if Kerr could draw greater encouragement from Gary Doherty, a player he has nurtured through the national youth teams he used to control. "He's a great motivator and his attention to detail has never changed," Doherty said of Kerr.
"We will all know everything about Cyprus and their game plan and then it's up to us to put our game plan into operation." Doherty admitted the players were aware of the media attention on Kerr - "we all read the papers," he said - adding that it would be "nice" to win for the manager who "has nurtured a lot of us through the years".
The Norwich utility player said Kerr could take great credit for the return of Roy Keane and had a record to be proud. "He's our manager and he has done a great job," claimed Doherty, his own memories of Cyprus good having won the European Under-19s Championships - under Kerr.Reuse content