Thomas Tuchel insisted denying Callum Hudson-Odoi a loan switch to Borussia Dortmund proved a 'very easy decision'.
Bundesliga giants Dortmund had offered Hudson-Odoi the chance to feature in his favoured left wing role, but Chelsea rejected any move out of hand.
Blues boss Tuchel revealed the Stamford Bridge club could not allow the 20-year-old to leave, with the young England star's ability to feature at wing-back vital in west London.
Hudson-Odoi notched his 100th Chelsea appearance in Saturday's 3-0 Premier League win over Aston Villa, where he featured at right wing-back, left wing-back and also left wing.