Yorkshire coach Andrew Gale is hoping for a quick resolution after four players were forced to stand down from Monday's T20 Blast defeat by Lancashire under coronavirus guidelines.
Matthew Fisher, Josh Poysden, Tom Kohler-Cadmore and David Willey all had to drop out - but only one of them has been tested for Covid-19.
"I'm hopeful that a text will come tomorrow morning and that they'll be back in the mix for the Durham game on Wednesday," said Gale, whose side were beaten by six wickets.
Earlier in the day, Yorkshire said they were "awaiting results of a Covid test which will determine future availability".
And Gale confirmed: "Only one player has been tested. The family member had symptoms, but that player has come into contact with the other players outside our cricket bubble.
"With the guidelines in place, the physios and club doctor said they couldn't take part in the game unless that one person tested negative. Unfortunately, it didn't come through.
"They were sat outside the ground until 5.30pm waiting on a text, but unfortunately it didn't come. I full expect it to be negative, but you just don't know. You have to be careful.
"I don't really want to get into who it was. It's just disappointing we had those four lads out. "
Yorkshire made 145-9, which Lancashire chased down for the loss of four wickets with 2.1 overs to spare.
"To have the heart of your team ripped out was always going to make it tough tonight. Add them to Dawid Malan being back and we'd have looked a strong outfit," Gale added.