Facing each other for the first time since that epic US Open match, Juan Martin del Potro defeated Dominic Thiem 6-2 7-6 in an hour and 42 minutes for his fourth win over the Austrian in as many matches and the second semi-final of the season. It wasn't the best possible match we could get, with del Potro who struggled physically and Thiem who once again showed his weaknesses outside clay and in the end it was the Argentine who prevailed thanks to a better serving and three set points saved in the second set tie break.
Dominic was 2-6 3-5 down when he started his comeback and he had a nice opportunity to send the match into a decider but it just wasn't to be for him, missing set points at 6-4, 6-5 and 7-6 and closing the match with a double fault in the 16th point of the tie break to send del Potro into the semis.
The Argentine played better on both the first and second serve and he faced just three break points, losing serve when he served for the win in the 10th game of set number two, and he converted three out of six break points he earned on the other side.
Juan Martin drew first blood in game three when Thiem netted a forehand and things went from bad to worse for the Austrian when he wasted a 40-15 lead in game seven to drop serve once again after a terrible shot from his forehand side.
Del Potro closed the set with three service winners and another forehand error from Dominic in game eight and he was hoping to continue in the same style in set number two. Thiem couldn't find his range and he sprayed another forehand mistake to lose serve at the start of the second set to find himself with a lot of work to do in order to get back on the scoreboard.
Del Potro saved a break point in game two and he served well in the next three games to open up a 5-3 lead, serving for the match at 5-4. Out of sudden, Thiem broke him at 15 and the match was still alive and kickin', with the momentum switching to the other side.
The Austrian earned two set points in the tie break after a double fault from del Potro but the Argentine saved them both and another one at 6-7 with an ace. Another ace gave him the first match point and he converted it with a double fault from Thiem, setting up the semi-final clash with Alexander Zverev.
Kevin Anderson scored his 10th victory of the season and seventh in a row after a 7-6 6-4 triumph over Hyeon Chung in an hour and 52 minutes, beating the Korean for the second time in as many matches. The South African served at 70% and he blasted 18 aces, facing seven break points in three different service games. He fends off six of those to keep the pressure on Hyeon who had to play against three break chances, dropping serve twice to end on the losing side.
We saw two good holds on both sides at the start of the match but Kevin was pushed against the wall in game three, facing four break points. He fends them off with three service winners and one from forehand and each player created a break point in games six and seven but the result remained on serve.
Returners had no chances in the last five games before the tie break where Anderson raced into a 5-1 lead with three mini-breaks. Hyeon won the next four points to get back on the level terms but Kevin fired a forehand winner to gain another lead at 6-5, sealing the set with a solid backhand attack in the following point for a 7-5.
With the momentum on his side, Anderson broke at the start of the second set with a deep return that Chung could only push into the net, and he raced into a 4-2 lead with three commanding holds (he hit 10 winners in those three games).
The time was slipping away from Chung and he broke back in game eight with a great return that landed just before Kevin's feet, leveling the score at 4-4 and preparing everything for another tie break. Instead of that, Anderson broke him again in the following game with a powerful forehand down the line and he sealed the deal when Hyeon sent a backhand long in the next game to book his place in the semis. Quarter-final results: