Johanna Konta crashes out of US Open after shock defeat by unseeded Aleksandra Krunic

British No 1 suffered a 4-6, 6-3, 6-4 loss to crash out of the year's final grand slam

Johanna Konta has been knocked out of the US Open by unseeded Serbian Aleksandra Krunic (Getty)

Johanna Konta arrived at the US Open as one of eight players who could have finished the year’s final Grand Slam tournament as world No 1 but left it in frustration after suffering a shocking first-day defeat.

Six weeks after reaching the semi-finals at Wimbledon, the 26-year-old Briton was beaten 4-6, 6-3, 6-4 by Serbia’s Aleksandra Krunic, the world No 78. Konta made far too many mistakes as 24-year-old Krunic brought back memories of her excellent run to the fourth round here three years ago, when she beat Petra Kvitova and Madison Keys.

The match bore similarities with Konta’s surprising defeat by Su-Wei Hsieh in the first round of the French Open earlier this summer. Although Krunic has a more orthodox style than Hsieh, the Serb’s unpredictable variations of pace and use of slices and drop shots appeared to trouble Konta, who is at her best when slugging it out with her opponent from the baseline.

Krunic, a slight figure who stands only 5ft 4in tall, can hit the ball with surprising power, but she reaped a regular dividend when she pulled Konta forward or forced the Briton to generate her own pace. Konta did not volley well and made far too many mistakes. In total she made 42 unforced errors to Krunic’s 36.

“I felt amazing,” Krunic said afterwards. “I’m happy with the way I played and the way I fought.”

When Krunic made her run to the last 16 here three years ago, Konta won only five games in losing to Shahar Peer in the opening round. However, Konta has been the one who has made the greater strides since then. The Briton has won three titles, reached the semi-finals of both the Australian Open and Wimbledon and risen to No 7 in the world rankings.

Konta was considered among the favourites to reach the final stages at Flushing Meadows (Getty)

Krunic, in contrast, has yet to realise her full potential, though she has shown flashes of her talent this summer, having beaten Jelena Ostapenko, the French Open champion, in the first round in Cincinnati earlier this month. Nevertheless, she had gone into this match having not beaten a top 10 opponent since the 2014 US Open.

Although Konta won the first set, it was clear from the start that she was not at her best. There were five breaks of serve in the opening set as the Briton struggled to build on a promising start, having led 4-1 with two breaks of serve.

Konta eventually won the first set but was soon struggling in the second. At 2-3 she just managed to hold serve after a game that lasted nearly 10 minutes, but at 3-4 she was broken, Krunic hitting a forehand winner on break point. The Serb promptly served out to love to level the match.

Krunic battled back from losing the first set to clinch a major victory (Getty)

At 1-1 in the deciding set Konta was broken again. At 30-30 she put a simple backhand in the net and then doubled-faulted. By now the alarm bells were starting to ring, though Konta retrieved the break immediately. Having hit some powerful returns, the Briton put herself in a position to take the game with a backhand winner.

When Krunic served at 2-3 and 15-30 Konta wasted a good chance to put her opponent under pressure when she hit a drive volley beyond the baseline. It proved to be a crucial moment. Krunic went on to hold serve and then broke to lead 4-3, hitting a backhand pass winner on break point after taking advantage of a weak volley by Konta.

Konta held on when serving at 3-5 and 0-30, but Krunic showed no nerves when she served for the match in the following game. Having gone 40-0 up, the Serb converted her second match point when Konta missed a backhand.