Port Vale assistant boss Mark Grew has been dismayed by the form of goalkeepers Stuart Tomlinson and Chris Martin this season.
The Staffordshire club currently have one of the worst defensive records in League Two, conceding 17 goals in 10 games, and have also let in five more in two cup matches.
Tomlinson started the campaign as first-choice goalkeeper but was dropped following the 3-2 defeat at AFC Wimbledon at the start of September.
Martin kept Vale's only clean sheet of the season in the recent win at Plymouth, but then conceded five times in his next two appearances against Bradford and Shrewsbury and was replaced by Tomlinson for the 1-1 draw at local rivals Crewe on Saturday.
"It's been frustrating for the goalkeepers and the staff. For me, they've both been disappointing," Grew told BBC Radio Stoke.
"They look at their own performances and they've been disappointed as well. We've worked hard, we've had long chats and discussed what we need to do. I thought Tommo [Tomlinson] did well on Saturday."