Tennis ace Serena Williams and teenage sensation Coco Gauff have been rallying together in preparation for their US Fed Cup first round qualifier tomorrow.

The US team also includes Alison Riske, Bethanie Mattek-Sands and the 2020 Australian Open champion Sofia Kenin who are set to host Latvia in Washington. 

The American duo, Williams and Gauff, are yet to face each other in a tournament. 

Williams is currently ranked at No 9 and Gauff who is making her Fed Cup debut at the age of 15 is ranked at a career high of No 51.

One fan wrote: "I could watch this all day!" Another agreed and wrote: "Wooow this is beautiful."

The US will be looking for a first Fed Cup title since 2017.

The Latvia team includes the 2017 French Open winner Jelena Ostapenko and 2018 US Open semi-finalist Anastasia Sevastova along with Diana Marcinkevica and Daniela Vismane. 

The first round will be taking place on February 7-8 at the Angel of Winds Arena in Everett, Washington.