Leeds boss Marcelo Bielsa sought to ease expectations after their 4-1 win at Championship rivals Derby County.
They led inside five minutes through Mateusz Klich's 20-yard curler, but Tom Lawrence soon levelled with a fierce, dipping free-kick.
Kemar Roofe's header restored the Whites' advantage as they continued to pour forward during an open first 45 minutes.
Rams manager Frank Lampard brought Bradley Johnson on at half-time in a tactical switch that did temporarily stem the flow - but Roofe's superbly-struck second and an Ezgjan Alioski header added further gloss to the scoreline.
Bielsa - speaking mainly via a translator - says his side were a "focused team".
He added: "The Championship is very long and it is not convenient to make conclusions now."
Roofe also said: "We didn't finish last season well at all and everyone was disappointed.
"But we're only two games in. We can't get carried away."
And Klich said, "I hope we keep going because it's a really nice way of playing football, but there are a lot of games to go.
"Last season, we also started good, but then we dropped off.
"I just hope this season is going to be better. But it's a very long way to go. We need to perform like we did in those two games, and we'll see."