Head coach Thomas Tuchel has acknowledged that Chelsea were fortunate to see out the final stages to beat Brentford on Saturday evening.
Trailing to a first-half Ben Chilwell strike, Brentford went the direct approach during the closing quarter to keep the Premier League leaders under constant pressure.
While the Blues managed to ride out the storm, Tuchel says that it felt like Chelsea were playing with one player less once Brentford had thrown more players forward.
Speaking to Sky Sports, Tuchel said: "In the end the last 20 minutes were suddenly a cup game. They had nothing to lose and they found momentum. It felt like we had one player less.
"We were not clear enough in the challenges. They found the belief and we focused too much on defending. I was very content with the first 65-70 minutes where maybe we should have scored more.
"It helps if we have Toni [Rudiger] or Thiago [Silva] to help calm the game down and with that first touch to counter the pressure. We trust the guys who are young, if you don't play you cannot get experience."
Chelsea have now collected 19 points from their opening eight matches, retaining their position at the top of the table.