DALLAS — Reilly Opelka faces potential discipline for his post-match comments about a chair umpire he called the “worst ump on tour,” the ATP said in a statement Friday. Opelka was angered ...

Reilly Opelka was competing against Cameron Norrie in the round of 16 tie at the Dallas ATP 500 event. The American tennis player had lost the first set, but later won the second set in a tiebreaker.