The 22-year-old midfielder was handed his fifth Premier League start of the season in the west London derby on October 19. However, he was hooked after just 15 minutes in the goalless draw.
It was later confirmed that Gallagher was replaced due to illness, but Potter has since confirmed that he trained with the squad.
The Chelsea boss was asked about his team news heading into a huge clash with Manchester United on Saturday, October 21. Potter replied at his press conference (per Football.London):
"We are still in the process of recovery. Pretty much as we were with Brentford. Conor [Gallagher] trained today so we will how he is over the 24 hours."
Potter has a few fitness concerns at the Blues, with Reece James and N'Golo Kante suffering long-term injuries.
Chelsea have been in excellent form ever since the former Brighton & Hove Albion boss took over, as they are unbeaten in seven encounters.
They will, however, be looking to bounce back from their disappointing draw with Brentford on Wednesday, despite having several big opportunities to break the deadlock. They currently sit one appoint above Manchester United in fourth-place ahead of their Stamford Bridge showdown this weekend.
Graham Potter 'very impressed' with Chelsea defender
During his pre-Manchester United press conference, Potter was also full of praise for Trevoh Chalobah, who has been in excellent form in recent weeks.
The 23-year-old has played every minute of Chelsea's previous three Premier League encounters. They have kept clean sheets in all of those games.
England are sweating on the fitness of several defenders ahead of the World Cup, including Reece James, Kyle Walker, Harry Maguire and John Stones.
Chalobah's experience of playing in a back three or five could work in his favor as Gareth Southgate must soon make a decision on his squad. Potter was asked if he felt the defender deserved an England call-up, to which he replied:
"I've been very impressed from day one. He wasn't starting in the first couple of games but acted perfectly. He is an impressive character, very focused on his football. He wants to play the game and wants Chelsea to win."
"We've had some problems but has stood up for us. He is performing at a really good level. He is playing every week for us so there is a decision for Gareth to make, not me."