MELBOURNE, Australia (AP) — Rafael Nadal has withdrawn from Spain’s opening match at the ATP Cup because of a sore back but says he hopes to return later in the week. Spain beat Australia in his absence. Top-ranked Novak Djokovic led Serbia to a 2-1 comeback win over Canada to open its ATP Cup defense. There are six tournaments this week to help players coming out of quarantine to prepare for the Australian Open. Sofia Kenin won her first match back at Melbourne Park since her Grand Slam breakthrough at last year’s Australian Open in another tune-up event.
