It was a perfect opening day for Aussie Spirit ©Softball Australia

Japan have made an impressive start to softball's Australia Pacific Cup in Blacktown.

Tokyo 2020-bound softball teams Australia, Japan, Mexico and Italy are facing Chinese Taipei and New Zealand, with the home nation fielding two teams - Australia A and the Aussie Spirit.  

Second seeds Japan were silver medallists the last time softball featured on the Olympic programme - in Beijing 2008 - and looked in imperious form at Blacktown International Sportspark in the Sydney suburbs.

The first game of the competition saw Japan play fifth-ranked Mexico.

The scoreboard was quickly moving, with the Mexicans taking a surprising 3-0 lead in the first inning.

However, that was as good as it got as the favourites hit back hard - eventually winning 8-3.

Chinese Taipei, ranked sixth, failed to qualify for Tokyo 2020, but were far too strong for New Zealand, coming through 7-1.

Australia A then took to the field for a remarkable match against rivals New Zealand, with Rachel Lack scoring in the first inning for the hosts.

But that was the end of the scoreboard action as Australia A edged the 1-0 victory.

Japan followed up their opening win with a superb first inning against Chinese Taipei, shooting out to a 6-0 advantage.

With the match all but over, they rounded out an impressive 8-1 success.

The game of the day saw Mexico take a 3-0 lead against Italy, but the Europeans pulled off a stunning comeback, with four runs in the sixth to win 4-3.

The all-Australian encounter saw Aussie Spirit defeat Australia A 4-1.

In the final game of the day, the Spirit defeated Italy 7-4 for their second win of the competition.

Qualification matches continue tomorrow.

The world's top-ranked side, the United States, are not competing.

After the tournament, Softball Australia will select 23 players to compete under the banner of the Aussie Peppers of Minnesota in the USA National Pro Fastpitch as part of their build-up for Tokyo 2020.