Laura Robson collapse seals first round exit, Jo Konta through

In an erratic encounter, which saw the pendulum swing between both players, Robson went down 3-6 6-3 7-5 at Flushing Meadows.

The Brit has seen her ranking plummet to 618 after missing more than 16 months with a wrist injury, but although she looked physically capable in Tuesday’s encounter, her mental fragility was exposed again.

"Any loss is tough but that one especially because, I mean if we’re being honest, I should have won," Robson said. "That definitely makes it harder and makes me more determined to work harder for the next one.

"I didn’t feel overly nervous. I just took 5 per cent off all my shots and that was enough to let her back into the match. She wasn’t going to give up. That 5 per cent made all the difference and it didn’t work out."

Robson also threw away a commanding position against Christina McHale at the Connecticut Open last week.

Earlier, Jo Konta impressed in ousting American wildcard Louisa Chirico 6-3 6-0.

"It looks good on paper but I don't really treat this win any differently from the previous 13," Konta told BBC Sport.

"I'm really happy I was able to deal with things out there and take my opportunities."

Aljaz Bedene also progressed when opponent Ernests Gulbis retired. Badene was leading 3-6 6-4 3-0 at the time.