The second day of the softball competition at the Olympics saw the two gold-medal favorites, the United States and Japan improve to 2-0 while Australia got themselves into medal contention with their first victory of the competition.

USA 1, Canada 0

Monica Abbott pitched a complete game, one-hit shutout while striking out nine as the Americans moved to 2-0. 

Team USA had chances in the first two innings, loading the bases in the first and having runners on first and third in the second, but Canada starter Sara Groenewegen got out of the jam both times.

The only run of the game came in the top of the fifth inning when Haylie McCleney singled with one out. After Janie Reed sacrificed her to second, Amanda Chidester singled her home.

Chidester singles in the only run of the game for Team USA/Photo: Kyodo News via Getty Images
Chidester singles in the only run of the game for Team USA/Photo: Kyodo News via Getty Images

A single and hit batter followed to load the bases, but Canada reliever Lauren Regula got out of further trouble by striking out pinch-hitter Bubba Nickles.

Canada had their only opportunity in the bottom of the sixth as Abbott walked Jennifer Gilbert and Groenewegen doubled to right-center as pinch-runner Joey Lye attempted to score.

A perfect relay from McCleney to Ali Aguilar to Aubree Munro gunned down Lye at home plate to preserve the lead for the Stars and Stripes.

Abbott worked a one-two-three seventh as the Americans have allowed just two hits over the first two games. 

Japan 3, Mexico 2 (8 innings)

Relief pitcher Miu Goto stranded five runners over the final two innings as Japan won the first extra-inning game of the tournament.

Japan manager Reika Utsugi left ace Ueno Yukiko on the mound in the seventh to celebrate her 39th birthday with what she hoped would be a complete-game victory, but the right-hander surrendered the tying run and left the game with two on and no outs.

"I was about done going into the last inning, but because it was my birthday, the skipper kept me in", said Yukiko. "It's really unfortunate I was unable to close it out, but the way everyone fought back, this win makes me extremely happy. This was a huge win for us."

Goto retired all three batters she faced in the seventh, striking out two, and when Japan failed to score, she struck out three more in the eighth to leave the bases loaded.

Unlike Mexico, Japan was able to score the runner who started the extra inning on second base. Captain Eri Yamada went to third on a ground out and scored on a game-winning bunt single by Mana Atsumi.

Japan celebrates their walk-off win over Mexico/Photo: Yuichi Masuda/Getty Images
Japan celebrates their walk-off win over Mexico/Photo: Yuichi Masuda/Getty Images

Japan's two-way star, Yamato Fujita, opened the scoring in the second inning with her second home run of the tournament. Mexico tied it in the fifth on a home run by Anissa Urtez, her first of the Olympics.

Haruka Agatsuma broke a 1-1 fifth-inning tie, only for the Mexicans to tie it 2-2 in the seventh on Urtez's RBI single off Ueno.

Australia 1, Italy 0

The OlmpyRoos evened their record to 1-1 as Kaia Parnaby took a three-hitter into the seventh. Jade Wall drove in the only run of the game with a single in the second inning.

Australia is in the win column for the first time in Tokyo/Photo: Koji Watanabe/Getty Images
Australia is in the win column for the first time in Tokyo/Photo: Koji Watanabe/Getty Images

Taylah Tsitsikronis doubled off of Italy starter Greta Cecchetti leading off the second, advanced on a groundout by  Tarni Stepto and scored on a two-out infield hit by Wall, who beat the throw to first after a diving backhand stop by second baseman Andrea Filler.

Italy falls to 0-2 in the competition and has yet to score.