Day 4 of the Rio Olympics has already started, but here are some highlights of events to expect today that you can watch through live stream.

Olympic fever has spread across the country and many have been glued to their screens to watch the world's greatest athletes excel at what they do best. It's now Day 4 of competition and some of the biggest names in U.S. sports will be competing in their respective fields.

NBC and its various sister networks like Bravo, USA, CNBC and MSNBC will be broadcasting the Olympics for almost the entire day, but if you can't watch it on TV, there are ways to live stream. Just go here to NBCOlympics.com and click on any of the green [LIVE] buttons to watch an event going on right now.

Here are some of the highlights to check out in Day 4 of the Olympics:

-Men's Tennis - 12 p.m. ET

Great Britain's Andy Murray will be playing a singles match against Argentina's Juan Monaco. Murray is the defending men's singles champion, having defeated the great Roger Federer in the 2012 London Summer Olympics. Murray's match against Monaco will be for the second round of play, as he hopes to advance in the tournament.

-Women's Tennis - 5:45 p.m. ET

Much like Murray is hoping to defend his 2012 Gold medal, USA's Serena Williams is hoping to do the same on the women's side. She is playing in the third round of the women's singles today, against Ukraine's Elina Svitolina. She and her sister Venus Williams suffered a devastating first round loss in the doubles tournament this year, and Venus was defeated in the first round of her singles match, so Serena is carrying the torch for the Williams family now.

-Women's Gymnastics - 3 p.m. ET

The U.S. women's gymnastics team, a.k.a. Simone Biles, Gabby Douglas, Laurie Hernandez, Madison Kocian and Aly Raisman, will be competing in the team final today. The team will be battling China, Russia, Great Britain, Brazil, Germany, Japan and the Netherlands.

-Women's Soccer - 6 p.m. ET

U.S. women's soccer, which features such all-stars as Hope Solo, Carli Lloyd and Alex Morgan, is competing against Columbia in this final day of the group stage of the tournament. After this, the teams will be in the knockout stage.