A set-up change for Lewis Hamilton after Free Practice 1 sent the balance of his Mercedes in the wrong direction at the Abu Dhabi Grand Prix.
The Englishman was only fourth best in the second session in Yas Marina after topping the opening 60-minute hit out.
He ended the day 0.6s away from Max Verstappen, his best of 1:25.761s less than a second up on his fastest lap in Free Practice 1.
By contrast, George Russell improved by 1.3s in the latter session, held in cooler conditions as the sun began to set.
“P1 felt pretty good. P2, balance was a bit quite a bit off,” Hamilton said.
“I made some changes between sessions one and two which weren’t the right ones.
“So a bit of a struggle in P2 just with a lot of oversteer, and that was mostly my limitation.
“We’ll make some changes overnight but, otherwise, we were relatively competitive.”
Mercedes has enjoyed an upturn in performance in recent races, highlighted by its one-two last time out in Brazil, headed by Russell.
There have been other strong showings too, with Hamilton in contention for victory in both the Dutch and United States Grands Prix.
That pace looks present again this weekend, though the seven-time world champion suggests Red Bull is still the team to beat.
“It looks a little bit closer,” he said.
“I think the Red Bulls look quicker here, which was expected – we didn’t expect this to be our strongest race.
“So we’ll work hard overnight. We’re generally right there so hopefully, we can put on a good fight”
Held in the dying sunset, Free Practice 2 offered the most representative running of the weekend, with Qualifying and the race set to be held at similar times on Saturday and Sunday respectively.
Understanding the tyres in those conditions was therefore of paramount importance.
“It’s really difficult over a single lap because all of the tight corners are in the last sector, so you’re trying to find that balance of get the most out of the tyre, not taking too much out in Sector 1, but making sure it’s still alive there in Sector 3,” explained Russell.
“Race run, [we’re] a little bit behind Red Bull.
“We know they’ve got a really slippery car down the straights, very efficient.
“On a circuit like this with two long straights and lots of slow-speed corners, this kind of suits them down to a tee.
“So pleased we’re much closer than we were let’s say at Spa, where it’s not too dissimilar.”