There is no shortage of must-see action on Day 4 of the Tokyo Olympics. The GOAT of gymnastics pulled out of the Team USA gymnastics finals after an "unfortunate" and "unusual" mishap, losing her first shot to medal at these summer games
Meanwhile, U.S. women’s national team secured a spot in the quarterfinals after a disastrous opening match against Sweden (followed by a happy rebound vs. New Zealand). And USA softball is undefeated no longer.
Without further ado, here are our 4 to Watch on Day 4:
DON'T MISS THE ACTION: For a complete rundown of all the day's events in Tokyo, visit the streaming schedule page for NBCOlympics.com. Watch every event live there, on the NBC Sports App and connected set-top boxes and catch the highlights in primetime on NBC.
1. Simone Biles Pulls Out of USA Gymnastics Final
The U.S. gymnastics team took silver in the women's team event after Simone Biles withdrew from the competition after the first event.
According to a statement from USA Gymnastics, Biles withdrew due to a medical issue. The organization said she will be assessed daily to determine medical clearance for future competitions. Biles' coach wrote to NBC after Biles' exit, "Physically she is fine. But she is done for the night."
Before her withdrawal, Biles had an uncharacteristically poor vault, and she failed to stick the landing. She bailed out of her Amanar and only completed a 1.5 twist on a 2.5-twisting Yurchenko, then took a big stumble backward on the landing.
After her vault, she could be seen being evaluated by Team USA trainers.
Despite entering the final event down by less than a point, the United States could not catch the ROC, who took control in the floor routine, finishing with a final total of 169.528 and winning gold. The United States finished behind the Russians with a score of 166.096.
Biles posted the third-worst score out of all the competitors in the vault with a 13.766. Simone Biles, a vault master, uncharacteristically failed to stick the landing. Jordan Chiles had the best score out of the Americans with a 14.666 and Grace McCallum had a 14.300.
Competing without Biles, Suni Lee stepped up on the uneven bars and the balance beam. She posted a 15.400, the best score on the uneven bars through three rotations. In the balance beam, Lee secured a score of 14.133.
2. America Wins 4 Medals in Swimming — Including Stunner by Alaska Teen Over Olympic Champ
Most eyes were on Lilly King and Ryan Murphy looking to defend their Olympic crowns Monday night — but a 17-year-old from Alaska stole the show.
American Lydia Jacoby pulled a huge upset over the highly favored Lilly King in the 100m breaststroke. Jacoby won the gold in 1:04.95. King, the defending Olympic champion, was half a second behind, finishing third. Tatjana Schoenmaker of South Africa captured the silver.
While there were four medals earned by Team USA in the pool on Day 4, Jacoby captured the only gold. Murphy finished third in the men’s 100m backstroke, not able to follow up his gold medal in Rio. His time was 52.19.
“Being third in the world is no shame, but obviously you want to go out and win, Murphy said. "That was the best I had today."
Regan Smith came in third in the women’s 100m backstroke with a time of 58.05. Kaylee McKeown of Australia won the gold and set a new Olympic record of 57.47 — that after the record was broken in three consecutive heats on Sunday.
The other American, Rhyan White, finished fourth.
After winning the bronze in the 400m freestyle, Connecticut's Kieran Smith couldn’t follow it up with another medal, finishing sixth in 1:45.12. British swimmers Dean Thomas and Duncan Scott finished 1-2, and Fernando Scheffer of Brazil won the bronze.
Monday night’s action also featured semifinal races for the women’s 200m freestyle, men’s 200m butterfly and women’s 200m individual medley.
3. Japan Beats U.S. Women's Softball 2-0 in Gold Medal Game
The U.S. women’s softball team lost to Japan 2-0 in the gold medal game of the Tokyo Olympics.
Team USA hit into a double play to end the sixth inning and stranded two runners.
Japan, which won gold at the 2008 Olympics, had a runner in scoring position in each of the first four innings before finally converting on an infield single in the fourth inning.
Japan added its second run in the top of the fifth inning.
The Americans, who were unbeaten entering the contest, had three runners in scoring position but have failed to capitalize.
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4. USWNT Wraps Up Group Play Against Australia
The United States women’s soccer team is headed to the quarterfinals after tying Australia 0-0 in its final game of group play.
With the tie, the United States finished second in Group G, going 1-1-1 in its three group games. The team won the tiebreaker over Australia based on goal differential, with the United States’ goal differential of 2 being better than Australia's -1.
In the match, Alex Morgan had a goal called back after VAR determined that she was offside. That was as close as the two sides would get to scoring. Goalkeeper Alyssa Naeher stopped the two shots she faced.
The quarterfinals for women’s soccer begin on Friday, July 30.