I wonder if Weston was worn out. his semi 3 set win must've been really tough.
He had to have been tired - that 3 set semi final was his second match of the day (after his match with Tony that morning). Two points were crucial for Brad:
1) The match point he did not convert in the second set against Philip Bester. He ended up losing that second set and needed well over an hour to finally win the match.
2) The break point he did not convert in the first game of the final against Roshan. His passing shot looked to be a clean winner, but clipped the very top of the net. He ended up losing that game and then getting broken in the next, and had to play the entire match from behind.
Change those two points and I think you have a different winner of the tournament. Brad is a veteran player and does not get rattled. Because Roshan, on the other hand, is under so much pressure to win and continue his quest to grind it out on the tour, it may have been difficult for him to overcome an early setback. Brad would also have had confidence being up and knowing that he beat Nima in a recent tournament.
And these are the things that make tennis such a great game.