Visser heads Chadwick in W Series practice at Zolder

Britain's Chadwick had won the opener in Hockenheim after leading both Friday practice sessions there and then qualifying on pole position.

(Reuters)

She was fastest again in Friday's first session but was beaten by former Red Bull junior Visser in the damp second at a circuit that hosted Formula One between 1973 and 1984.

"Having not been here before, I had to learn the circuit and try to get into it quite quickly. So I think there was a bit more potential there, but it’s going to be close tomorrow," said Chadwick.

The six-race series has attracted plenty of interest, with television deals putting it out to a free-to-air audience in countries like Britain, as a concept aimed at helping women up the motorsport ladder.

The series winner will collect $500,000, with prize money down to 18th place.

(Reporting by Alan Baldwin, editing by Pritha Sarkar)