Potter’s assistant Billy Reid took Albion’s pre-match press conference on Friday and will take charge of the team at the King Power Stadium on Sunday.
The 58-year-old was a manager in his own right for eight years at Hamilton before linking up with Potter at Swedish club Ostersund in 2013, and has worked with him ever since.
“Graham had a rough night last night and tested positive this morning so he didn’t take training,” said Reid.
“We’re not too sure how it will work yet, we are yet to decide, but I will certainly be linked up to him at home.
“We never did it at Swansea but we had to do it twice at Ostersund and I think we won one and lost one.
“I was a manager in Scotland for eight years, so I know what to expect. This is the Premier League and it is a big step up, but I feel fine about it. I’ve worked alongside Graham for nine-and-a-half years now, so nothing will change too much, we’ll try and keep things normal.
“The players are in a good place and we will look forward to Sunday.”
Brighton, who came from behind to draw with Chelsea in midweek, will face a Leicester side who suffered a devastating home loss to Tottenham on Wednesday.
Steven Bergwijn scored twice in injury time as the Foxes blew a 2-1 lead to lose 3-2.
“We were actually at the game so we saw it,” said Reid. “It looked as though they would win the game but then obviously in the last 30 seconds lost it, so I think they will be hurting and I think that will make them even more ready for us.
“They are missing a few players but they will be dangerous. Brendan Rodgers’ teams are always well organised and Leicester are a top-eight or top-six team, so once again we will have to be at our best.
“We are not too sure who will be available for them, but whoever it is they have a strong squad.
“Brendan I know through his time in Scotland where he did an unbelievable job at Celtic, winning everything, and since he came to Leicester he has made a big, big impression as well. We will be going up against a top coach, make no mistake about that.”