"We are three points behind Fiorentina, so we may need to win all three remaining games. Lyon have got to play Fiorentina as well, so somebody will drop points," said Johnson.
"We would be happy with three wins but Lyon are a fantastic team who score a lot of goals at home.
"Any away game in the Champions League is hard. We must stick together and fight for each other. Hopefully we can keep a clean sheet and come back with three points."