Serena Williams’ former coach Rennae Stubbs awkwardly lambasted Coco Gauff’s ‘bad technique’ in the presence of her coach Brad Gilbert.

Speaking with Gilbert on ESPN, Stubbs said: “Where is Coco’s confidence? There’s no second serve, that’s the sign, and that’s a problem.

“Under pressure, bad technique breaks down and her technique is… it’s hard for me to say because Brad [Gilbert] is sitting here.

“Her technique, the elbow is too low, the grip is a little weird as well. So it’s hard for her to get that nice first serve and then the same or similar second serve.”