Michael Phelps Wins First Gold Medal in Rio as His 3-Month-Old Son Cheers Him On

Getty Images

Make that 19 career gold medals for Michael Phelps!

The celebrated swimmer picked up his first gold medal of the Rio Games on Sunday night, winning the 4x100m freestyle relay alongside his American teammates. Phelps swam the second leg of the race, and helped fend off a French team who touched out the U.S. to win gold in the same event at the London Olympics four years ago.

Phelps was accompanied by fellow American speedsters Nathan Adrian, Caeleb Dressel, and Ryan Held in the race, and had his own adorable cheering section in the crowd. His mom, Debbie, was joined by Phelps’ fiancee, Nicole Johnson, and the couple’s 3-month old son, Boomer, who cheered the Olympic champ on as he raced to yet another gold medal in his storied career.

WATCH: The Entire 2016 U.S. Olympic Swim Team Bonds in Epic Carpool Karaoke Video

The race came just moments after another impressive American victory in the pool, as rising superstar Katie Ledecky won the 400m freestyle in commanding fashion, shattering the world record (her own) and touching out the rest of the field by more than five seconds. Her teammate, Leah Smith, also clinched bronze in the event.

Getty Images

RELATED: 9 Team USA Swimmers to Watch in Rio (That Aren’t Michael Phelps)

This is just the start of what will likely be many visits to the top of the podium for both Phelps and Ledecky. Phelps is still slated to swim the 100m and 200m butterfly, as well as the 200m individual medley, while Ledecky will look to defend her gold medal title in the 800m free -- an event she has dominated on the international stage since winning gold in London -- and contend in the 200m free, a new event for her this time around.

Go Team USA!

WATCH: Ashton Kutcher and Mila Kunis Stoked For Roles as 'Arm Chair Olympians'

Related Gallery