ABU DHABI -- Sebastian Vettel was left surprised by the gap to Mercedes in qualifying as he settled for third on the grid for 2017's finale.
Vettel had topped FP1 on Friday and stayed within 0.14s of Hamilton's quickest time in the evening session. However, 24 hours later, he was over 0.5s behind Valtteri Bottas' eventual time.
The German admitted the performance gain he expected on Saturday simply did not materialise.
"Yesterday and this morning I was quite confident that Lewis in particular was very quick, like in FP3, and [we] should get more in the direction of yesterday but it was more the other way around," Vettel said. "Mercedes in general were very quick, Valtteri put in a mega lap so the gap was bigger than I expected.
"For tomorrow though I think the gap will shrink, I hope so anyway, then we will see what we can do. But for tonight we'd love to be closer."
Abu Dhabi has traditionally been one of Mercedes' strongest circuits in the V6 turbo era but Vettel is confident he can put the world champions under pressure when the lights go out.
"I think it was a good session but a bit of a shame to be that far back in qualifying so tomorrow we will see with race pace I think we can be a bit closer but they have been very, very strong."