Spain advanced to the quarterfinals of the ATP Cup even before Rafael Nadal stepped on to the court Wednesday at the Perth Arena.
Spain, which won the Davis Cup in Madrid with a victory in the final over Canada, stayed in the hunt for its second international team victory in seven weeks when Roberto Bautista Agut beat Japan's Go Soeda 6-2, 6-4.
Japan needed to beat Spain 3-0 in order for the Nadal-led team not to advance to the Final Eight in Sydney beginning Thursday. Nadal later had a 7-6 (4), 6-4 win over world No. 72 Yoshihito Nishioka, committing 36 unforced errors.
"I always enjoy sharing important moments with friends, and we had a lot of success during our entire careers playing for our country in Davis Cup," Nadal said. “So for us it's a good start, to be able to be qualified for Sydney already. The conditions will be different, and a three-hour time (difference). There's a lot of things we need to adjust to, and the period of time to make it happen is very short."
Spain, Serbia, Australia, and Russia all enter the knockout stages unbeaten as group winners. Australia face Britain in Thursday's opening quarterfinal at Sydney Olympic Park Tennis Centre, before Russia takes on Croatia, which progressed as Group E winners on Wednesday without even hitting a ball.
Previously winless Poland's surprise victory over Austria eliminated world No. 4 Dominic Thiem's lineup. Hubert Hurkacz's 3-6, 6-4, 7-6 (5) victory over Thiem sealed Austria's fate after Kacper Zuk beat Dennis Novak 5-7, 7-6 (3), 6-3 in the opening match in Sydney.
In other matches on the final day of group play, Serbia, which had already qualified for the quarterfinals, beat Chile in Group A. Dusan Lajovic beat Nicolas Jarry 6-2, 7-6 (3) before Novak Djokovic defeated Cristian Garin 6-3, 6-3.
The six group winners and two best second-place finishers advance to the finals in Sydney.
The remaining three quarterfinalists will be decided on Wednesday night, with six countries still in the running. Two of those quarterfinalists will be the best two pool runners-up. South Africa and France meet in Brisbane trying to finish second behind Serbia in Group A.
Belgium and Canada, both with 2-1 round-robin records, could also qualify for the last eight teams.