Day hopes shorter swing leads to long spell of success

Jason Day kicks off 2017 at the US PGA Tour tournament of champions on Thursday ranked number one in the world, and the Aussie is hoping his painstaking rehab of a back injury keeps him at the top.

Speaking to reporters on Tuesday at Kapalua, Hawaii, where the elite tournament tees off on Thursday, Day said he was "cautiously optimistic" he could avoid a repeat of his injury-plagued 2016.

"I'm just trying to get stuck back into the process, trying to get better," said Day, who said he spent the three months since back pain forced him out of the Tour Championship in September working to recover.

"I feel better about my body, feel better about my game, feel better about my swing," Day said. "I feel better mentally than I did the second half of last year, so I'm hoping for very good things this year."

Day said he has worked on shortening his backswing in a bid to alleviate pressure on his back.

He hopes the new approach will see him end a seven-month title drought.

"Seven months, it really is a long time," he said.

Health issues weren't the only problems that Day felt threw him off track last year, and in 2017 he said he would stop worrying about being thought a slow player and return to the methodical ways that helped him put together a sparkling run of seven wins in 17 starts.

That included three USPGA titles last year -- but none after the Players Championship in May.

Day admitted that he let concerns about his pace of play pull him out of his normal game plan.

"I wasn't as deliberate going into a golf shot. Gathering the information, I wasn't as deliberate," he said. "Obviously, everyone wants to speed up the game. Obviously, that's a big subject in golf, to speed up the game.

"You don't want to be classed as a slower guy, but thinking about it now, when I was playing and competing really well I forgot about that stuff," he said.

"I just have to make sure I am deliberate but still respect other players."

While the USPGA Tour's 2016-17 season officially got under way in October, this week's event marks a return to action for many top golfers.

Jordan Spieth was coming off a stellar 2015 that lifted him to number one in the world when he won the trophy last year. The 23-year-old Texan returns this year ranked fifth in the world.

World number three Dustin Johnson, who won the US Open on his way to USPGA Player of the Year honors, is a strong contender, having lifted the trophy at Kapalua in 2013.

And sixth-ranked Japanese Hideki Matsuyama arrives in Hawaii on a hot streak that includes four victories in late 2016, including the Japan Open and World Golf Championships HSBC Champions in China in October, the Taiheiyo Masters in November and the Tiger Woods-hosted Hero World Challenge in the first week of December.