Leo Messi scored a wonderful free-kick in the first half which proved to be the difference between the two teams.
"It was a very important match in that sense," replied Valverde when asked by reporters what the win does for the title race.
"It isn't the same to be eight [points clear], than two. It isn't definitive, obviously, but we have taken a step. We'll see what the future holds."
Barcelona were largely in control of the match at the Camp Nou, particularly in the first half, and Valverde commended his players for seeing out his game plan from start to finish.
"[I'm] proud, above all, of how we have competed," said the coach. "In matches of this kind, we have responded with certain guarantees and today has been like that.
"Everything has followed the script.
"It was hard to get [the win] because they have a great defence.
"Little by little we have been moving forward. We knew that, as the game went on, it would become more difficult because of the week we have had.
"They haven't had clear chances but you're uneasy because they have great strikers. We suffered because, to beat Atletico, you have to suffer."