Thiem won in four hours and 10 minutes against the Spaniard in what was described before the match as a thriller.
It very much lived up to that billing; but three tiebreaks which were expertly won by the Austrian saw him produce the goods and continue a magnificent tournament.
In the first set, Nadal was 6-5 up and had chances to go 30-0 up on his serve; but Thiem sent down four first serves including two aces to send it to a tiebreak. This is what made it interesting as Thiem very much had the momentum claiming the first set in this tiebreak 7-3.
Nadal seemed to regain the momentum in the second set though going 4-2 up against Thiem; as he looked to get a set on the board. The latter tied the match up though at 4-4 after Nadal had hit a sloppy forehand into the net to face three break points and after that he hit a double fault.
Thiem streaked to 40-0 in the requisite game and put the onus back onto Nadal at 5-4 up. Nadal claimed a valuable hold in the next game pouncing on a backhand error from Thiem and hitting a second ace of the game to make it 5-5.
It went to another tie break from there and once again Thiem produced brilliance winning it 7-4 to go two sets up in a tight game but one he was leading 2-0.
Nadal finally got make into the match earning two set points; after a brilliant rally on the second point to make it 2-1 and claim the second 6-4.
It was all or nothing in this next set and it was Nadal who seemed to gain back the momentum in the latter half of the contest making it 6-5 as he looked to force a five set thriller; but Thiem sent it to a tiebreak which as the match showed isn't the best predicament for Nadal.
He claimed the match from there after initially wasting match points, he hit it in style keeping him pinned to the back of the court and Nadal hit it into the net to give Thiem the superb victory.
Thiem will now play Alexander Zverev in the semi finals, who beat Stan Wawrinka in 4 sets earlier today.
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