In the quarterfinals , he faced second seed Alexander Zverev in Zverev 's first major quarterfinal , defeating him 6 -- 4 , 6 -- 2 , 6 -- 1 .
However , Thiem was able to take the fourth set 6 -- 4 to win the match .
In the quarterfinals , Thiem faced second seed Alexander Zverev in Zverev 's first major quarterfinal , defeating Thiem 6 -- 4 , 6 -- 2 , 6 -- 1 .
However , Thiem was able to take the fourth set 6 -- 4 to win the match .