What it's like to lead against a No. 1 seed at the US Open

I'm finally back in California unwinding after what was an emotional, hectic and exciting three weeks in the Big Apple. While a second round finish may not sound particularly notable, three rounds of qualifying, weather delays and a solid performance on Arthur Ashe Stadium made it one of the most promising weeks of my career.

I received zero freebies in my draw this year—from the first round of qualies until second round of main, my opponents brought a high standard of tennis and competed fiercely. While I was frustrated at times that I was unable to close out matches more efficiently (four of my five matches were three-setters), I was proud of the way that I competed under the immense pressure of the final Slam of the season and the watchful eye of a pro-American crowd.

After a dramatic qualifying round against Naomi Brody, I felt myself tear up for the first time ever after a win. The combined effect of the disappointment of having been passed for a main draw wildcard, the pressure of holding my seed in qualifying, and the knowledge that the difference between first round qualies and first round main draw was a staggering $45,000 had taken its toll. I think I was feeling a lot of pride in that moment, although relief was perhaps my most dominant feeling.

In the first round of main draw, things got off to a great start. Leading 6-0, I was feeling confident and prepared to put my foot on the gas pedal to speed into round two. However, a long bathroom break from my opponent, some dodgy weather and a refreshed bout of 'it would be really nice to win this' anxiety made for a quick 1-6 set. After trailing 15-40 on my serve in the first game of the third set, I rallied to a crucial 1-0 lead in the third—a lead that I would be asked to sleep on, in light of worsening rain.

Sleeping on an unfinished match is the absolute worst feeling and anyone who tells you otherwise is lying. Admittedly, I found it a bit easier with my 1-0 edge than I have previously with tied or trailing scores, but it's just never a fun time. My boyfriend Jack and I tried to get my mind off of tennis as much as possible, firing up TV and some good food for what was left of the evening. Our strategy seemed to work well because when I returned in the morning, although nervous, I played determined, efficient tennis to finish the match 6-1 in the third. Phew.

Now, the fun part. If you had told me after my first round qualifying loss in Cincinnati that I'd be at 3-3 in the third with the No. 1 player in the world on Arthur Ashe Stadium in a matter of two weeks, I would have had my doubts. But there I was, an unlikely thorn in the side of one of the favorites to take the trophy in Flushing Meadows.

For the first set and a half, I felt unstoppable. Experience had taught me to keep my focus firmly beneath my visor and to hold on tightly to my routines in such a big venue. While I recognized that it might prove difficult to maintain my level and focus down the stretch, I felt oddly calm and... was it "comfortable"?

Perhaps my third round matchup with Serena Williams in Laver Arena earlier this season and a previous run-in with Ashe had amounted to more than L's on my Win-Loss record. I tried not to question it, as I continued to dictate play and impose my will.

Long story short, my moment was not to arrive that day. While I displayed some of my best tennis on the biggest court in the world against the current best player in the world, it wasn't yet to be. I fell just short in a 2-6 6-3 6-4 loss that was, in many ways, more inspiring to me than any win could have been. I had risen to the challenge, I had proven what I was capable of, and I wouldn't allow myself to take steps backward.

A lot of people have asked me since the match, "How was your coach, Roger Smith, after the match? Was he sooo excited?" When I finally saw him after my cool down, media and some physio attention, his reaction was as simple as it was perfect: He shrugged and said, "Told you." That's how you know you have the right man for the job.