American veteran Venus Williams was sharpening her reactions for the barrage of big serves she can expect in her Wimbledon semifinal against British favourite Johanna Konta today, going through a relentless practise routine on the eve of battle.

The 37 year old spent 45 minutes on the dusty Aorangi Park practice courts yesterday, hitting back serves delivered at high velocity by a male hitting partner.

Konta tops the ace leaderboard in the women's singles with 28, one more than Williams.

Against Simona Halep on Tuesday, Konta offered up only two break points in a match lasting two hours and 38 minutes.

Following her quarterfinal victory over Jelena Ostapenko, Williams said she would be expecting a close battle with her British opponent.

"I think we play a very similar style," she said. "Aggressive, serve well, return well, very solid off the ground. So really it's just about playing that game better and see where you find openings on that day."

Williams is bidding to win her sixth Wimbledon singles title and eighth grand slam.

Meanwhile, Sam Querrey sent defending champion Andy Murray crashing out of Wimbledon and reaching his first grand slam semifinal.

Querrey, the world number 28, won 3-6, 6-4, 6-7 (4/7), 6-1, 6-1. World number one Murray's challenge petered out when he began limping off his right leg.

Querrey will face either Gilles Muller of Luxembourg, who stunned Rafael Nadal in the fourth round, or Marin Cilic for a place in the final.

"I'm still in a state of shock. I'm glad I hit that last serve in," said Querrey.