India, Aug. 17 -- Alexander Zverev's impressive campaign at the Cincinnati Open ended on Saturday after a defeat to world No. 2 Carlos Alcaraz in the semifinal. En route to the 4-6, 3-6 loss, Zverev took a medical timeout after bouts of dizziness and breathlessness resurfaced due to the high temperatures in Cincinnati.

The German had cruised through the opening half of the tournament, beating Nishesh Basavareddy, Brandon Nakashima, and Karen Khachanov. Barring the Russian, he took down all his other opponents in just two sets, keeping his hopes alive for a maiden Cincinnati Open title.

However, during his match against Ben Shelton in the quarterfinal, as he was a set and a break up, he suddenly motioned for help and needed on-court medi...