Pakistan v India World Hockey League 26 June 2015 Live
Going into the contest, both India and Pakistan's strikers have been erratic and wayward.
India have won their first two outings against France (3-2) and Poland (3-0) but van Ass' wards were far from impressive.
Pakistan, on the other hand, managed to beat Poland 2-1 before being outplayed by Australia. The Australians hammered Pakistan 6-1 after being 1-1 at half-time.
Indian captain Sardar Singh said even though their Rio Olympic berth was secured, they wanted to take this opportunity to produce some positive results ahead of the World League Finals. "We want to win against Pakistan ahead of the game against World champions Australia the next day."
For coach van Ass, to be a part of an Indo-Pak contest, is a new experience.
"It's going to be my first experience of an India-Pakistan hockey encounter. But during the 2010 World Cup in Delhi, I saw the excitement it causes," the former Dutch national coach said.
The showstopper encounter between Asian Games champions India and Champions Trophy silver medallists Pakistan has raised the stakes in the diamond city of Antwerp.