Reece James to start for Chelsea in Blackburn League Cup tie
Chelsea's captain suffered a hamstring injury after their game with Liverpool at Stamford Bridge on August 13th and only returned to action in their last two matches off the bench.
"I can confirm he is going to start," Pochettino told reporters on Tuesday. "I want to confirm only one player but it's good for the team, it's good for him to start from the beginning of the game."
With just three wins in 10 Premier League games, Chelsea are in 11th place, 14 points behind leaders Tottenham Hotspur.
They lost their last match 2-0 at home to Brentford on Saturday and their season targets may need to change.
"It's difficult to say now. The most important is the game, to go step by step," Pochettino said.
"To go through the competition (League Cup) is important, then go to Tottenham and receive Manchester City to get momentum."
Pochettino takes Chelsea to face his old club Spurs in the league on Monday but the Argentine won't let that influence his team selection for the League Cup game on Wednesday.
"We are not going to take decisions tomorrow for Monday because I think we have time to recover," he said.
"We are going to try to take it very seriously like always as I think it is a competition we can go through."
The five-time League Cup winners beat AFC Wimbledon and Brighton & Hove Albion in the previous rounds.