Serena Williams reckons there is plenty more to come after she cruised into the second round on opening day at SW19.

Williams eased past Nueza Silva 6-1, 7-5 on Centre Court with a minimum of effort.

And the number two seed has warned her rivals that once she gets warmed up, she could be unstoppable.

Williams said: "I thought I could have played a ton better than that today.

"But I feel like as the tournament goes on and progresses, I'll get there.

"I'm insatiable - I always want more.

"I always feel like I could improve or change something.

"I honestly think that when I lose it is on my racquet - it's up to me to decide whether to win or lose.

"I have always said that when I play my best tennis it is hard for anyone to beat me."