For a second-straight match, the world No. 9 found himself needing to win two straight sets after a sluggish first.
Del Potro was out of sorts when this match started, having trouble with the way Kohlschreiber was mixing things up. The German was moving del Potro around as much as he could, and he was also making excellent use of the drop shot.
The big Argentine would not say down for long. The new set invigorated del Potro, who took out some frustration on his racquets. Settled in, he took care of business in the second set to force a decider.
The third set was even more straightforward, as del Potro began to play his best tennis right when Kohlschreiber started to play his worst. Del Potro's forehand was at its fearsome best late in the match, and Kohlschreiber was unable to handle it.
The icing on the cake for the world No. 9 came when he gave Kohlschreiber a taste of his own medicine, utilizing a drop shot of his own to help hold serve and go up 4-2 in the third.
Match point from Del Potro vs. Kohlschreiber:
The German was a tough opponent for del Potro, who will now face Milos Raonic in the semifinal. The two giant hitters have faced each other only three times in his career; the Canadian holds the 2-1 edge. Their most recent meeting came in 2017, in Delray Beach, which Raonic won 6-3, 7-6 (6).
Del Potro, 29, has made only three ATP World Tour Masters 1000 finals in his career, and he has lost every one of them. Considering his talents, del Potro probably should have won one of these titles by now, and he knows it.
With a win, del Potro could potentially face Roger Federer in the final. Earlier this week, Del Potro said that "any chance to play with Roger would be great."
A possible matchup is now looking like a reality, but both men have one more hurdle to clear.
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