Speaking ahead of Tuesday's game, Mauricio Pochettino said: "It's about having a different approach on the game. I was disappointed — the players were disappointed — at half-time [against Preston North End].
"We reviewed what we need to improve but there's not much time to work as our priority was to recover our physical condition. Middlesbrough have good players and a good coach, and it will be tough with atmosphere and no VAR.
"It is very important, important to get a very good result, knowing that it is going to be a tough game. We need to start in a different way. It was a good example, the first half against Preston, it is going to be a competitive game."
Chelsea are travelling to Championship side Middlesbrough on Tuesday night in a 2023/24 Carabao Cup semi-final first-leg clash.
The Blues secured their place in the FA Cup Fourth Round last week, beating Preston 4–0 at home although all four goals came in the second half.