As the four players made their way down the steps at Queen’s Club, there was no doubt that the raucous roar from the 9,000-plus crowd was meant just for Williams.

But there was no big reaction from the former world number one, who gave a brief wave before starting her warm-up and locking in for the task ahead.

Williams said on Sunday that winning was “not important” on her return, but it was inevitable that the competitive spirit would kick in for the great champion.

With every point that the pair won, Williams raised a clenched fist before marching back to Mboko to talk tactics, while she let out a huge celebratory roar when the teenager reacted quickly to slam down a volley at the net.

The seven-time Wimbledon singles champion’s powerful groundstrokes looked as good as ever, while her serve still had the same sting, with one coming in at 120mph to cause a stir among the crowd.

Williams, however, was modest about her performance. When asked for a report card, she said: “What do you think? A C-minus?”

Her overhead shots looked a tad rusty, while she was slightly off the pace with her movement at times and Mboko did a sublime job covering from the baseline.

“Don’t be too hard on yourself,” Mboko said. “I thought she was moving great.”