Johannesburg: World number five Rafael Nadal has insisted that he will be 'very competitive' in the upcoming season after enduring a modest 2015 season.

The 14-time Grand Slam champion, who slumped to 10th in the rankings in June, failed to win any of the sport's four grand slams for the first time since 2004 but finished the year on a much improved note, making couple of finals before reaching the semis at the season-ending ATP World Tour in London.