The event attracted approximately 40,000 fans to the Tokyo Dome, the Shellcom Sendai and the Fukushima Azuma Stadium - with the latter one of the venues in which baseball and softball will be played at the Games in Japan's capital.

Hosts Japan completed a three-game sweep over world number one-ranked United States in the women's event sanctioned by the World Baseball Softball Confederation (WBSC).

"This has been a great warm-up for our sport’s Olympic comeback in 2020, with top quality competition and great fans throughout the All-Star Series," Japan captain Eri Yamada, an Olympic gold medallist at Beijing 2008, said.

"Every athlete dreams of playing at the Olympic Games in front of a home crowd.

"I am sure that Olympic baseball and softball will be among the highlights of Tokyo 2020."

Japan took the first game of the All-Star Softball Series, defeating the US 4-0 in front of more than 15,000 fans at the iconic Tokyo Dome.

Their three-run first inning was key, with Beijing 2008 Olympic gold medal-winning pitcher Yukiko Ueno sealing the win in four innings of work.

Game two was tied at 1-1 until the home nation scored four times in the fifth inning to claim a 6-3 win at Shellcom Sendai.

Japan completed the sweep over the US with a 2-0 win at Fukushima Azuma Stadium.

Yamada hit a two-run home run to support Ueno’s pitching performance.

"The team and I always look forward to the opportunity to play here in Japan," Amanda Chidester, a member of the US team, said.

"There is always a large fan base that is extremely passionate, which makes it that much more exciting for the Olympics to be played here in 2020.

"Match-ups like this and the support we have from all ages show what both baseball and softball have to offer the Olympic Games, and Japan is the perfect place to kick-start softball’s return to the Olympic platform."

The French women’s national softball team were observers throughout the Japan All-Star Softball Series, along with representatives of the French Baseball and Softball Federation (FFBS).

The day before the opening match, the Japan Softball Association and FFBS signed a Memorandum of Understanding (MoU) aimed at supporting the growth of softball at every level in France and, ultimately, securing softball’s place at the Paris 2024 Olympic Games.

"This was an exciting opportunity to come to a heartland of softball and train with some of the world’s best players," Eloise Tribolet, a member of France's team, said.

"The experience will help the French national softball team take the next step in our development.

"The Olympic Games returns to France in the FFBS's centenary year, 2024.

"Playing at the Games in front of a home crowd would be an incredible way to celebrate the 100^th anniversary of French baseball and softball."

As a first concrete output from the MoU during their stay in Japan, the French women’s national softball team had the opportunity to train with some of the world best talents.

They participated in sessions with Japan Softball League’s Bic Camera Takasaki and Taiyo Yuden teams, as well as with softball legend and WBSC Executive Board member Taeko Utsugi.

France's coaches also observed the training techniques that have earned Japan and the US the top two places in the WBSC softball world rankings since 2015.

Baseball and softball will be returning to the Olympics after being axed following Beijing 2008.

They were added to the Tokyo 2020 programme at the 2016 International Olympic Committee Session in Rio de Janeiro.