The Uruguayan front man bagged his 11th goal of the season when he headed in a Jamie Carragher flick-on late in the second half at Stamford Bridge to cancel out John Terry’s first half header.
And Johnson has praised the striker’s current form, claiming the 25-year-old is ‘scoring for fun’ at the moment.
He told Liverpool’s official website: “Luis is a great player and he is doing a fantastic job for us.
“He is scoring goals for fun at the moment and the longer he does that the happier we will be.”
The England defender also admitted Liverpool were delighted with the result against Chelsea and that Brendan Rodgers’ team, who are now unbeaten in their last six Premier League matches, are improving game by game.
“If we had been offered a point before the game we probably would have taken it,” he added.
“Playing away at Stamford Bridge, it was always going to be difficult. Chelsea are very strong at home and we were expecting a tough game.
“We have great spirit in the dressing room and a lot of heart. We always fight to the death. We did that and got our reward. Of course we want to be winning games but it was a good point for us.
“Everyone can see we are starting to improve and if we keep playing well I am sure the results will come our way.”