U.S. Open underway amid drug testing scandal

The U.S. Open — the last tennis grand slam of the year — is underway in New York. Another gripping tournament is expected with an open women's competition and three stars in the men's draw who all look evenly matched.

However, one of those men, Italian world number one Jannik Sinner, has been in the headlines after he was cleared to play despite appearing to test positive twice for a banned substance.

Tennis journalist and author Christopher Clarey joins host Scott Tong for more.