Basketball 3x3 officially made its Olympic debut Friday night, and several games turned out to be thrillers as the action got underway.

Here's a recap of some of the day's top contests.

(W) ROC def. Japan 21-18

ROC took the early lead over Japan and never relinquished it. At one point ROC led by eight, but Japan orchestrated a late push to make the final score close. Japan eventually came within a two-pointer of tying the game, but ROC's Yulia Kozik nailed a two-pointer to end it with 25.6 seconds remaining. The ROC women took the victory and changed their focus to China. Quite the finish to the first-ever Olympic 3x3 game.

(W) China def. Romania 21-10

Despite the lopsided final score, China's tilt against Romania was much more exciting than advertised. The game was fairly even early on, but China eventually started to pull away. With 1:08 to go, China's Lili Wang sunk a two-point shot to end the game and secure the victory.

(M) Serbia def. Netherlands 16-15

Serbia's men had quite the challenge against the Dutch after defeating China in Session 1. This was a defensive showdown that saw both teams struggling to generate offense. Despite falling behind 14-12 with just over two minutes remaining, Serbia rallied to score four straight one-point buckets to take the lead. The Netherlands' Dimeo van der Horst attempted a two-point shot to win the game as time expired, but his shot hit the backboard and missed the basket. It was a nail-biter, but Serbia got the W.

(W) Italy def. Mongolia 15-14

The Italians kicked off their first contest of the tournament with a thriller against Mongolia. After taking a 13-7 lead, Mongolia stormed back and put together a 6-1 run. Italy ultimately pulled away late and staved off another late surge from Mongolia to win the game.

(W) USA def. France 17-10

The United States and France have become quite familiar with one another recently. Team USA beat France at the Big Twelve International Tournament, and now they look to be fierce rivals as the women's 3x3 tournament kicked off. Led by Stefanie Dolson, the U.S. played stingy defense against the French club and limited them to go just 8-for-35 on shooting attempts. Dolson finished the game with 7 points and 6 rebounds.