The ex-Liverpool tactician also bemoaned the number of games his side have had to play over recent weeks and believes his squad lack strength in depth.
He told reporters: "We are playing more games than anyone. In some positions we have only two or three players, that's the reality.
"After the Africa Cup of Nations, and when we get Eden Hazard back, we'll be able to manage a bit better.
"I'm really focused on my job. We know we are training well and preparing properly, and that's my job."
|CECH TARGETS EUROPA LEAGUE
|4.75||Fernando Torres is 4.75 with bet365 to open the scoring against Reading
He added: "The positive is that we are still scoring goals and conceding less than in the past, but we still need to improve.
"I was really pleased with John Terry against Brentford after not playing for such a long time.
"My focus is to improve the team and keep the players believing that we can win. I like managing top sides and this is one."
Chelsea travel to face an in-form Reading side on Wednesday as they look to remain in the Premier League title race, but Benitez is aware his side face a tricky test.
He continued: "Reading will be a tough game, we know they play with high intensity and we have to be ready."