British number two Jack Draper was knocked out of the Miami Open in the second round with a 7-6 (7-3) 7-6 (7-0) defeat by Reilly Opelka.

The 24-year-old lost two tie-breaks to the big-serving American, who wrapped up the win inside 93 minutes.

Draper had headed into the tournament after an impressive run to the quarter-finals at Indian Wells – featuring a win over Novak Djokovic – following nearly eight months out with an arm injury.

However, he struggled against the powerful 6ft 11in Opelka, ranked 67th in the world, who fired down 25 aces and 47 winners.

Defeat leaves Draper at risk of slipping further down the rankings going into the clay-court season having surrendered his spot as British number one to Cameron Norrie this week.

Elsewhere, Katie Boulter progressed to the third round at Miami Gardens when Denmark’s Clara Tauson retired during their match through injury.

The British number three let a 5-3 lead slip as Tauson won the first-set tie-break 7-4, before she battled back to take the second set 6-4.

Boulter won the first game of the third set only for Tauson to decide she could not continue.

“It was a complete battle – some ugly tennis and ugly conditions as well, but you have to find a way,” Boulter said.

“Unfortunately she couldn’t finish but it is what it is. It’s never the way you want to win, but happy to be through to the next round.”