When the Wimbledon winner stepped onto the court Monday night, she was wearing an outfit and shoes from her new EleVen label.
Williams has become the latest celebrity to join forces with budget-minded retailer Steve & Barry's. The deal was announced Thursday, ahead of the tournament she's already won twice.
Williams is enjoying a career resurgence with her fourth win at Wimbledon earlier this summer, but she's played in fewer tournaments the past few years, largely because of injuries.
2What did she do in that newfound spare time? Attend fashion classes. She's on track to receive a degree from the Art Institute of Fort Lauderdale at the end of the year.
"I love fashion and the idea that I'm using my design education to actually create clothes and footwear I will wear on and off the court is a dream come true for me," she said in a statement.
Howard Schacter, the Steve & Barry's chief partnership officer who previously arranged deals with basketball player Stephon Marbury, golfer Bubba Watson and actress Sarah Jessica Parker, said active wear for women was one area lacking in the company's offerings.
"When we saw the success of our previous partnerships, we looked at other sports that provided an opportunity to do exactly what we've been doing on the basketball courts and golf," said Schacter.
Tennis, he said, seemed an ideal match because there is an off-court lifestyle associated with it.
EleVen will offer athletic wear, casual wear and footwear. Williams is wearing the V-Court pro sneaker at the U.S. Open.
"This partnership is the most analogous to Marbury because it's about on-the-court high performance as well as casual, active street wear," Schacter said.
The initial 120-piece collection will be available in November but a couple of hundred pairs of the V-Court will be sold Friday at the Manhattan flagship store.
Even though no item at Steve & Barry's costs more than $19.98, Schacter said enough research, development and technology went into the gear to give Williams the tools she needs during competition.
"It's far from having our fingers crossed that the performance is there. We gained a lot of knowledge through the Starbury brand and have consulted outside experts about performance."
Williams' comeback win at Wimbledon was "icing on the cake," Schacter said, but the fashion deal was made at the end of last year.
At the U.S. Open on Monday, Venus beat Kira Nagy of Hungary 6-2, 6-1, in a match that was highlighted by a Grand Slam-record 129 mph (203 kph) serve. Her sister Serena finished off a full opening day with a forehand smash that downed German teenager Angelique Kerber 6-3, 7-5.
"We'll still be partners with Venus long beyond her playing days -- same as Marbury," he said. "This goes beyond performance on the court."