Unseeded Russian Karen Khachanov advances to US Open semifinals after hobbled No. 28 seed Alexander Blockx retires in third set
Khachanov advances to face the winner of Wednesday’s prime-time match between No. 1 seed Alexander Zverev and unseeded Botic Van De Zandschulp.
<p>Khachanov advances to face the winner of Wednesday’s prime-time match between No. 1 seed Alexander Zverev and unseeded Botic Van De Zandschulp.</p>