Sam was a set up (losing 3 points on her serve only) and a double break up in set 2, now 4-4, just broken to love.
Last week she was a set and a break up, playing very well, when first her UE count went through the roof, the her serve completely disintegrated (US commentators points, not mine), and she lost in 3.
I hope this is just a blip, as she ought to win this at a canter, but it's a shame when you get yourself close to the finish line that these lapses happen. Fingers crossed everyone