Monica Puig, of Puerto Rico, leaps in the air after defeating Petra 

Kvitova, of the Czech Republic, during their semfinal match. (AP Photo/Charles Krupa)

Fans unfurled the Puerto Rican flag on the railing of the Olympic tennis venue. Soon after came the "Monica" and "Vamos!" chants that culminated with Monica Puig's upset victory in the Rio Games.

Puig defeated two-time Wimbledon champion Petra Kvitova of the Czech Republic, spurred on a by a vocal crowd that was thrilled at the propsect of the U.S. territory winning a gold medal for the first time.

Puig advanced to the gold medal match with the victory. Her joy could not be contained as a Kvitova shot in the third set went long and she leaped in the air in celebration. People also chanted "Monica, yo voy a ti," which translates roughly to "Monica, I believe in you."

"The stadium," she said, "was buzzing the whole time."