Chelsea head coach Sarri concedes he did not want to use Hazard at the Sinobo Stadium, but the Blues’ lacklustre showing forced his hand in the second-half.
Marcos Alonso’s late header saved Chelsea’s night, with the Blues now expected to complete the job in next week’s second leg and reach the semi-finals.
Sarri’s men face Liverpool at Anfield on Sunday in a key battle in their bid for a top-four Premier League finish, with Hazard doubtless now not as fresh as originally planned.
Asked if he had always planned to bring Hazard off the bench, Sarri replied: “No, at the beginning of the match I wanted him on the bench because I thought that, probably, the match was really very difficult.
“Probably I’d need to use him. Of course, if at the end of the first half we were 1-0, I wouldn’t have used him.”
Asked if Hudson-Odoi will start, Sarri said: “Oh, I don’t know. But in my opinion he needed to rest. And so, in this match, he was out.
“But of course he is in my mind for the next match, but I have to see the last two training (sessions).”