The former director general of the Scottish Crime and Drug Enforcement Agency, Graeme Pearson, who is now Labour's justice spokesman, is among six candidates vying for the nomination for two seats up for grabs in Ayrshire.
However, when local members got the candidates' personal statements last week, Pearson's name did not appear on his own pitch.
The documents have had to be re-sent days before the vote takes place next Sunday. The internal contests for the Carrick, Cumnock and Doon Valley seat and the Cunninghame South seat are gender twinned, meaning that one man and one woman have to be selected.
Party sources say the two favourites on the male side are Pearson and Joe Cullinane, a councillor whose father Jackson is Unite's political officer in Scotland.
As part of the process, the local party sent each candidate's personal statements to members last week. But Pearson's biography appeared on the back of another candidate's declaration - former MSP Irene Oldfather - without his name or picture.
William Crawford, a Labour councillor in East Ayrshire, said: "I just think we make things difficult for ourselves."
A Labour source said Pearson had been disadvantaged: "Graeme's statement didn't even have his name or photo on it, and it looked like it was page two of Irene Oldfather's statement."
Another source said: "Folk are not happy at how this has been handled."
Around 300 members are eligible to vote. The party has resent Pearson's statement.
Pearson, who said he had made no complaint about the process, said: "I think it was an administrative oversight that will be repaired." He was elected as a List MSP for the South of Scotland in 2011.
An SNP spokesperson said: "If Labour cannot organise a selection contest, it's no wonder they cannot win an election. Instead of squabbling with each other they should be fighting for the communities of Scotland facing Westminster austerity."
A Scottish Labour spokesman said: "We've got robust selection procedures in place and local members will pick a candidate they believe will serve their communities."