Top-seeded Ryan Harrison has a spot in Saturday\'s 18s semifinals, but Rhyne Williams (12) of Knoxville, Tenn., and Austin Krajicek (5) of Bryan, Texas, are waiting to finish their match, which was interrupted by a cloudburst Thursday afternoon.
Krajicek won the first set 6-1 but Harrison was leading the second 4-1 when the match was suspended.
The winner will play Harrison, a 6-4, 6-2, winner over Bradley Klahn (7) of Poway, Calif.
"Fortunately I got an early break on the first game," said Harrison. "He ended up breaking me back, but I immediately broke him back to get the game in the second.
"From then on out, when I went up 4-3 serving in the first set, I made a commitment to myself that if he was going to beat me, he was going to have to break my serve, whenever I made three or four first serves a game.
"The only game he broke me in, I missed all six first serves."

The top half of the 16s semifinals field is set with Bob van Overbeek (5) of Boca Raton, Fla., taking on Jordan Cox (7) of Duluth, Ga., on Saturday.
Both won their quarterfinals matches today, with the bottom half of the draw playing in the quarters on Friday.
Van Overbeek defeated Raymond Sarmiento (9) of Fontana, Calif., 7-5, 6-2, using his big serve to his advantage.
"(Sarmiento) was serving very well and I wasn’t getting that many opportunities,” said van Overbeek. “I just wanted to try and hold my serve. I’ve played him in practice and sometimes he’ll give you a few easy mistakes.
"I was hoping for that on his serve,"
With the first set tied 5-5, van Overbeek broke Sarmiento, then served for the set, winning on an ace.
In the second, Sarmiento was broken twice before pull ing to 5-2. On his second match point, van Overbeek won on an ace.

Cox advanced by beating Clay Thompson (11) of Venice Beach, Calif., 6-2, 3-6, 6-2.
"I thought I was still in (the second set)," said Cox. "I had one loose game where I got broken, played a couple of loose points and he started playing a little better on my service game.
"I only got broken once (in the second set), so I wasn’t unhappy about it,"

Source: USTA Nationals Staff