World sport: Mercedes blame ‘procedure’ after tyre investigation following Lewis Hamilton’s win, Venus and Serena battle at US Open

Mercedes have blamed the tyre-testing procedure for the controversy that followed Lewis Hamilton’s Italian Grand Prix victory.

The British driver’s win was called into question because one of his tyres was below the minimum recommended pressure before the race.

But stewards took no action after their investigation, and Mercedes’ F1 boss Toto Wolff said the tyres had been measured outside the correct period by the sport’s governing body.

“It is about the procedure when you measure the tyre,” he said.

Venus and Serena Williams will battle it out in the US Open quarter-finals, after the latter beat 19th seed Madison Keys.

World number one Serena is three wins away from the first calendar Grand Slam since 1998.

A year ahead of the Rio Paralympics, organisers believe the Games will break records.

Over 4,300 athletes from 178 countries will compete next September in Brazil, and International Paralympic Committee hope to see their biggest ever event.

And Wales’ World Cup hopes have been dealt a double blow, with Rhys Webb and Leigh Halfpenny both being stretchered off in Saturday’s win over Italy.

Webb injured his ankle, while Halfpenny suffered knee damage late in the game.