Chelsea manager Jose Mourinho has indicated that he is in no rush to include some of the club's academy players in his first-team squad.
The Blues have won the Under-21 Premier League title and the FA Cup Youth Cup this month, but the majority of the successful squad have yet to feature in the top flight.
Defender Tomas Kalas started two of Chelsea's last three Premier League fixtures, but Mourinho has hinted that it may take time before other fringe players follow the Czech centre-back into contention with the first team at Stamford Bridge.
The 51-year-old told Yahoo! Sport during a Twitter Q&A: "I want it in the right time. I don't want them to come and not to succeed."
Midfielder pair Nathan Ake and John Swift, who started in the Under-21 Premier League final against Manchester United on Wednesday, also featured for Chelsea during the final weeks of the season.