Norway's Casper Ruud declared on Wednesday that the world number one ranking could be his as early as the Australian Open in January.The 24-year-old had a chance to top the rankings when he took on Carlos Alcaraz in the US Open final this year, but the Spanish teenager won in four sets to take the title and with it the number one spot.Ruud said a good run for him at the Australian Open could be enough to become number one."If there is maybe one time that it could happen again, it's actually in the near future," the world number three said ahead of the inaugural United Cup mixed-teams tournament. "If I have a good trip I can be in a position (to become number one) again." But Rudd, who also made the French Open final this year, remained philosophical about his chances of reaching the sport's summit."It gives me motivation to keep going and know that you were very close at one time, but maybe that will be the closest you will ever be," he said."Maybe you'll get it, and maybe you will be in a close position another time in your career."I think last season has shown me that I have the potential if I continue to do the right things, work hard, I can be in that position again, or it can never happen - you never know in this sport."Norway begin their United Cup campaign against Brazil in Brisbane on Saturday, with Ruud's opening match against Thiago Monteiro on Sunday.