Britain's Heather Watson saw the chance to claim a morale-boosting win slip by as she lost to Romanian 21st seed Simona Halep in round one of the US Open.
Halep, 21, won 4-6 6-4 6-2 in two hours on Court 11 at Flushing Meadows to take her unbeaten run to six matches.
But Watson had victory in her sights at 6-4 4-4, 40-0, only to drop five points in a row and the next four games.
"I knew she wouldn't give it to me and she didn't, and I didn't make first serves on any of those game points," said a tearful Watson.
"That game was extremely important and once I get a few matches under my belt, I'll learn how to play those points smarter and take my time.
"I think that's why it hurts a lot, because I was so close. But if I keep making these opportunities for myself, I'll take some."
Watson went into the match as the underdog after seeing her ranking slip from 39 in February to 76 following a bout of glandular fever.
Halep, in contrast, is at a career high of 19 in the world after winning four tournaments in 2013, the most recent of which came in New Haven on Saturday.
However, a possible hangover from that successful run and a newly aggressive Watson game plan almost saw the British number two home.
Watson has been working with coach Jeremy Bates in recent weeks and has talked about how she plans to play more attacking tennis.
It was evident from the start as three heavy forehands helped her to an immediate break, before the same shot dug her out of trouble from 15-40 in game five and then brought her to set point.
Halep looked flat after her recent exertions, handing over the set when she found the net, and threw her racquet in anger after Watson saved two more break points early in the second set.
After breaks were swapped in games five and six, Watson looked to have settled and was closing in on victory at 4-4, 40-0, only for some free-swinging by Halep to bring on an attack of nerves.
After four points went against her, Watson double-faulted when facing break point, and it proved to be the pivotal moment of the match.
Halep overcame her own nerves to level the match and took control of the decider as Watson's serve and forehand deserted her.
Watson got one break back at 3-0 down but handed it straight back, to love, with a double-fault.
"I played better than I have been," Watson added. "I was playing one of the hottest players on tour right now; she made a lot of balls.
"I thought I played a good two sets and (in) the third set my fitness let me down a bit; I was cramping in my legs. I was bit tense in the way I was moving and hitting the ball.
"All in all, I'm pleased with how I played but I had my chances and I had an opportunity to win that match in two sets. But she's got the confidence and she won the points when it mattered."