ZANDVOORT (Netherlands) — Formula One is back after its summer break, with every sign the championship could go down to the wire as the chasing pack seeks to overhaul teenager Kimi Antonelli and his Mercedes.

The Dutch seaside resort of Zandvoort is hosting its last-ever Grand Prix and it promises to be action-packed, with an inaugural sprint race and changeable weather keeping the paddock on its toes.

AFP Sport picks out the key things to watch:After storming to the chequered flag six times in the first half of the season, 19-year-old Kimi Antonelli enjoys a 50-point lead over his nearest rival, seven-time world champion Lewis Hamilton.

But recent results have shown that Mercedes are not unbeatable and team boss Toto Wolff admitted his rivals were gaining ground.

“We have left points on the table, our rivals have reduced the performance gap, and we know the second half of the year will demand more from us than the first,” said Wolff ahead of the Dutch Grand Prix.

Antonelli salvaged a third-place finish in Hungary before the break but acknowledged it was a case of “damage limitation” and predicted a “big fight” in the second half of the season starting in Zandvoort.

Mercedes have never won at Zandvoort, noted Wolff. “This is our final opportunity to change that.”