The Blues lost 4-1 away at Newcastle last weekend but could be boosted by the returns of both Nkunku and Romeo Lavia, who have yet to debut since their summer transfers.
Nkunku and Lavia have trained ahead of Brighton but will have to pass late fitness tests before they are included.
"We need to assess tomorrow and then decide, they are close and tomorrow we will make a decision," Pochettino said.
"Lavia is maybe more difficult, but we need to assess Christopher Nkunku tomorrow."
The Argentine described the defeat last week as his "worst of the season" and branded his players "soft".
He admits Chelsea risk falling behind in the race for the Champions League if that manner of performance continues but he's urged the club to keep faith, and added: "If it is mathematically [possible], we need to believe it is realistic.
"It is another thing that will be tough to achieve, [qualifying] for European competition, but it is still there.
"Now, the most important thing is not to see the end of the season but to see the process and improve every day. That's the most difficult thing in this process; it is to be focused on today and not tomorrow. That's one aspect we were working on this week."
Pochettino explained that Chelsea's inconsistency is partly down to his team's tendency to implode.
He said: "It was a tough week for everyone but I am very happy because I think they reacted very well.
"After you watch the game, it was worse than my feelings after the game. I was tough with them inside and outside [in the media].
"But that was my feelings with them, because I think our approach was wrong so we take responsibility too.
We are our own worst enemies and need to focus on ourselves.
"It was a good week to realise what we need to improve, to be more consistent and mature. We didn't do things we cannot afford not to do in this process. I am very, very happy so far, even if it was tough in training and our meetings.
"But sometimes these situations help you improve. It's not the opponent, we can see it against Tottenham, Manchester City and Newcastle.
"You could easily say the one we were most likely to take points against was Newcastle because they had to play Paris Saint-Germain three days later, which could have been a distraction.
"Okay, we beat Tottenham and we lost against Newcastle. We are our own worst enemies and need to focus on us. If we are in a good place, we will compete in a good way and Brighton will not be a problem."