World No1 Roger Federer returns to the court to defend his Indian Wells title this week, fresh off the back of a doubles knock-up with Microsoft founder and billionaire Bill Gates.

The Swiss partnered the American business magnate and philanthropist in Monday night’s Match for Africa 5 exhibition in San Jose, which raised $2.5 million for the Roger Federer Foundation.

In an evening of entertainment in front of a 15,000-strong SAP Center crowd, Federer and Gates joined forces – in a repeat of their charity match in Seattle in 2017 – and faced World No10 Jack Sock and NBC Today Show host Savannah Guthrie in a celebrity encounter to raise funds for children’s education in Africa.

After that, the 20-time Grand Slam winner took on Sock in a light-hearted best-of-three sets singles clash, with the 36-year-old triumphing 7-6 (9) 6-4.

Federer has 1,000 points to defend at the BNP Paribas Open and needs to reach the semi-finals in California to ensure he stays atop of the rankings.

If he fails to do so, Rafael Nadal will reclaim the No1 spot for the fifth time in his career on March 19 ahead of the Miami Open – another tournament in which Federer is reigning champion – in just over two weeks’ time.

Federer is the favourite to win both titles and claim the American swing ‘Sunshine Double’ yet again – and is helped by the fact Nadal is ruled out of both events with a hip injury, joining the likes of Stan Wawrinka, David Goffin, Novak Djokovic and Andy Murray on the sidelines.

That leaves second seed Marin Cilic, Bulgarian Grigor Dimitrov and young gun Alexander Zverev as Federer’s main challengers whilst Juan Martin del Potro and Kevin Anderson also pose a big threat on the fast hard courts.

Top seed Federer, who has received a first-round bye, will bid for a 98th career title when he gets his campaign under way this week.