Former Buckeye Hunter Armstrong wins Olympic gold in 4x100m freestyle relay

Watch Olympic highlights in the player above.

PARIS (WCMH) -- Former Buckeye swimmer Hunter Armstrong scored his second Olympic gold medal after an impressive swim in the 4x100m freestyle relay final.

The Dover, Ohio native swam the third leg for the U.S. team and his impressive second 50 meter split of 46.75 seconds, the fastest time on the team, put Caeleb Dressel in position to cruise to the first gold for Team USA at the Paris Olympics.

This is the first time Armstrong won gold while racing in the final, with his Tokyo gold medal in the medley relay earned as a swimmer in the preliminary race. The Americans ended the first day in the pool with three medals, one of each color.

In the highly anticipated women's 400m freestyle final, Australia's Ariarne Titmus made quick work of Canada's Summer McIntosh and Team USA's Katie Ledecky to earn her second straight gold in the event. Ledecky's bronze marked her 11th Olympic medal.

Australia's second gold of the night came in the women's 4x100m freestyle relay with an Olympic record performance by the four-woman team. The victory earned Emma McKeon her 12th overall Olympic medal. Team USA got the silver just at the end with Simone Manuel out swimming China's Qingfeng Wu.

Germany's Lukas Maertens took home the first swimming golf of the games in the men's 400m freestyle. Australia's Elijah Winnington took silver with South Korea's Woomin Kim taking the bronze.

In the opening semifinals, USA's Gretchen Walsh set a new Olympic record in the 100m butterfly with a time of 55.38 seconds. She will be the favorite in tomorrow's final.

On the men's side, Nic Fink qualified for the 100m breaststroke final with the fourth fastest time in the semifinals. Fink is the world champion in the event and will be aiming for his first Olympic medal on Sunday.