Spain’s Davis Cup captain Albert Costa says Rafael Nadal “is worried” about his constant injuries, although the former top-ranked player is confident of getting back to his best form.

Costa says Nadal “is worried about his physical state but he’s working every day to get better” after another knee injury forced him out of the Australian Open and has sidelined him for Spain’s Davis Cup series against Switzerland next week.

Costa says Nadal’s dip in form over the past year is nothing to worry about because he “has achieved everything. It’s normal, after 22 years and winning everything, to have some down time.”

Nadal helped Spain win a second straight Davis Cup in December after a season plagued by injuries.

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