Red Bull’s Max Verstappen topped the timesheets in both FP1 and FP2, while McLaren’s Lando Norris was second in the evening session after third in the first.
Mercedes’ Valtteri Bottas went second quickest in the first session but was down in fifth under the lights, while Hamilton went fourth and third.
The Briton found himself 0.235s back on pace-setter Verstappen in the second to fuel hopes that Red Bull can truly take the championship fight to world champions Mercedes this year.
The Dutchman was also quickest in pre-season testing at the same circuit, when Mercedes endured a litany of problems.
However the seven-time world champion admits Red Bull have the early edge going into FP3 and qualifying on Saturday, and insists he’s delighted to see former team McLaren – without a title since Hamilton’s 2008 triumph – enjoying such fine pace.
Speaking to Sky Sports F1, Hamilton said: “We thought Red Bull would be as fast as they are if not faster. We know they’re leading at the moment.
“McLaren are looking great and it’s great to see them taking a step. It’ll be interesting to see how the long runs are.
On Mercedes’ struggles, the 36-year-old continued: “I definitely do [feel like we’ve taken steps forward]. Coming into this weekend we’d done a lot of work over the past week.
“I think we have taken a step forward but we still have more to do. With tyres and downforce reduced, the global balance has just shifted and it wasn’t where we wanted.
“I know that we still have a hill to climb but we’re staying positive.
Red Bull’s Verstappen meanwhile reflected: “Of course different conditions again compared to testing. It’s been alright. Good feeling in the car.
“Of course there’s still things to look into, tyre-wise as well, and a bit of balance tuning. Overall I’m pretty happy.
“Still tomorrow is again a different day. Even more windy, which with these cars is quite tricky. We’ll have to try and be on it. But a good start to the weekend.”
Asked if McLaren could be greater challengers to Red Bull than Mercedes, the Dutchman added: “I don’t think so. I still expect Mercedes to be the strongest Mercedes-powered car.”