It's highly likely to see 3 sets today. Phau is playing a solid tournament with 2 wins against very strong players such as Becker and Almagro, both with 2:1 result.
Sam Querrey dropped one set to Gicquel and today he'll probably do the same.
There is the matter of tie break which is likely to happen, so we can expect over 21 even if it stays in 2 sets!
I expect Querrey to win 2:1, but Phau has a good chance too.

They played once before and Phau won!
25/09-08 Beijing, China R16 Asia Hardcourt outdoor Phau, Bjorn 2:1 57 63 64

Good luck!