Johnson refuses to think any further than beating Lyon on Wednesday night.
He said: "It would be a disaster for this club not qualifying for the knockout stages - but it's not something we are thinking about.
"We have still got to believe we can do it. We don't even want to start thinking about he Europa League.
"It will be no consolation at all. It's not the aim and it's not the plan because we want to be in the Champions.
It is one of the main reasons why players want to play for a big side."