Pochettino was main person behind success of this Chelsea because he has done good job and keep things on good level which helps Maresca for having good end of his first season at coach of Chelsea which is having strong case of ending their season in top five clubs even nine matches remaining and things can take changes, but their case is good for keeping this momentum.
Title race is already ended due to big lead of Liverpool while Arsenal is also set for keeping their spot as they are also having 58 points which are good even their injuries worries and workload hurting them badly, but they have done good job in this season. Many teams were able to have good performance which increase competitiveness and challenges at the top even few teams are had decline into their performance like Aston Villa and Bournemouth, Brighton is always amazing club.
I don't believe Pochettino is the sole reason for Chelsea's success. Team success is a collective effort, not just the work of an individual. That said, while Chelsea are in contention for a top four finish, they must avoid any form of complacency and be more clinical in front of goal and ensure they keep a well defensive stability to secure the desired result. Otherwise they risk missing out on the top four spot.