Williams is snapped getting into the taxi during her charity run. Photo / Splash News
Tennis star Serena Williams has been spotted getting a cab to the finishing line of her own 5km run, which was raising funds for her charity foundation.
Williams was seen stopping near the 2km mark of the Serena Williams Live Ultimate Run South Beach 2015 event in Miami where she jumped into taxi. The car then sped to the finish line.
Her sister, Venus, who was also taking part in the charity run, was able to complete the run to the end.
Serena had been one of 3000 runners pounding the pavement along Ocean Drive and through the Art Deco district of Miami Beach.
The 34-year-old top athlete was wearing an orange Nike T-shirt, black leggings and sneakers for the run but added a touch of her signature style with sparking earrings and matching ring.
She appeared to start the run well on Sunday morning but by around the two-kilometre mark, witnesses at the event say they saw her climbing into the yellow cab.
It is not yet known why Williams used a cab to complete the majority of the charity run, but it is likely that a previous playing injury is to blame.
In October, the top-ranked player announced she was taking the rest of the year off to recover from a series of injuries.
She was forced to withdraw from her two final big tournaments, saying she needed time to heal from the physical injuries and the disappointment of losing out in her bid for the Grand Slam.
In a previous statement she admitted she had injured her knee and elbow this year and did not want to jeopardize her career by playing injured.
"It's no secret I've played injured most of the year - whether it was my elbow, my knee, or, in the final moments after a certain match in Flushing, my heart," Williams said, referring to the semifinal match which she lost against Roberta Vinci in the United States Open.
Williams pulled out of China Open in Beijing and the season-ending WTA Finals in Singapore at the end of the same month.
"I want to compete as well as I can as long as I can," she said. "So I'm taking a proactive step and withdrawing from tournaments in Beijing and Singapore to properly address my health and take the time to heal."
It is possible she feared one of her old injuries was flaring up in the five-kilometre run and decided not to risk further damage by pulling out and getting a cab.
Meanwhile, the star - currently ranked number one in the world in Women's Tennis - was chosen as one of 13 women who represent "outstanding professional, social, cultural, sporting and artistic accomplishment" for the 2016 Pirelli calendar.
For the first time the calendar includes women of varying shapes and sizes who are not professional models.
For its 43rd edition, Serena posed nearly nude, joining comedian Amy Schumer, writer Fran Lebowitz, Selma director Ava DuVernay, artist Yoko Ono, and rocker Patti Smith - all of whom were photographed by Annie Leibovitz.
The DailyMail.com reached out to Serena Williams who is yet to respond.
Money raised from the run, the second such event that Williams has hosted, goes to the Serena Williams Fund which supports a wide variety of causes.
In the past the foundation has helped build schools in Africa, fund college scholarships in New York and supported efforts to tackle the gun problems on America's streets.
The event was open to the public and had three events; the 5k, a quarter marathon and a children's event. The walk-up entrance fee for the quarter marathon was US$60 ($89).