Americans celebrate on-court feeling of independence

In the lead-up to July 4, America's Independence Day, a few star players were asked what makes them feel independent and free.

The feeling of independence is a big one in tennis because it's such an individual sport.

"I mean, it truly is one of the only sports where you're out there on your own," Sam Querrey said. "I do enjoy the battle, having to figure it out on your own. You know, that's what makes tennis unique."

Querrey has mastered independence at Wimbledon, as he knocked out No. 5 seed Dominic Thiem in the first round. He then eased past Andrey Rublev on Thursday.

Serena Williams, one of the most recognizable athletes on the planet, also values independence.

"It's one thing I love about tennis, is you're basically on your own out there," she said. "You just have to be independent and it's you and your opponent. You win or you lose, yeah. I love that feeling."

She's also safely through to the third round.

July 4 is a day for barbecues, pool parties and fireworks in the United States, but in London, it's about embracing independence on the court.