Ellen MacArthur says her bid to break the west-east solo trans-Atlantic speed record hangs in the balance. The British sailor is travelling from New York bound to the Lizard Point off the south-west coast of England and is just two hours off schedule.
But she told BBC Sport: "The toughest part is coming up and it really could go either way at this stage.
"But I'm confident I can do it. I only have two hours to make up so it's going to be really tight."
MacArthur is chasing a time of seven days, two hours, 34 minutes, 42 seconds set by Laurent Bourgnon in 1994.
And she is expected to arrive in England in the early hours of Tuesday.
 | The most undisturbed sleep I've had so far is 40 minutes, so it's beginning to get to me  |
Her boat, B&Q, must cross the finish line by 00:44:42 GMT to set a new world mark. She admitted the rigours of the challenge were taking their toll.
She said: "It's pretty tiring - the most undisturbed sleep I've had so far is 40 minutes. So it's beginning to get to me.
"But it's not affecting me too badly. I just have to hope the weather conditions stay on my side."