EXPERIENCE

Experience is a crucial factor when it comes to the Premier League. Newcomers in the Premier League generally take a while to settle down owing to the fast and physical aspect of the game. With Bakayoko arriving only in the recently-concluded transfer window, Matic's five-year experience in England would certainly have been more useful to Chelsea.
Also, considering the fact that Bakayoko is quite inconsistent and requires a better midfield partner to cover for him on occasion, Matic is definitely a better choice. Bakayoko at 22 still has a long way to go to be compared to the Serbian powerhouse, considering the 28-year-old's vast experience in the Premier League. Only time will tell whether he can surpass the Serb in the upcoming seasons.
United's midfield now certainly looks rock solid with Matic in the holding role, giving Paul Pogba the license to roam and help in the attack. If United do continue their form throughout the season, they might end up winning the league. In the meantime, the Londoners are left with nothing but to rue their blunder.