大象传媒

Clare Balding introduces coverage from the Twickenham Stoop as Harlequins host Castleford in the fourth round of the Challenge Cup. The 12 Super League teams enter the competition at this stage, and this game is the only all top-flight tie in this year's draw. Castleford have won the famous competition four times but the last time was more than 20 years ago, and they exited the tournament at this stage last year at the hands of Bradford. Commentary from Ray French and Jonathan Davies.