Three-time major winner Jordan Spieth believes Saudi Arabia's multi-million pound investment in golf is a threat to the PGA Tour but believes it will benefit players in the long term.

Next month's Saudi International was previously on the European Tour but is now the flagship event on the Asian Tour, which is also launching 10 new events backed by €176m from the Saudi government's Private Investment Fund.

Last month the PGA Tour gave players permission to play in the event on condition they made future commitments to the AT&T Pebble Beach Pro-Am in California which is scheduled to take place the same week.

"I think certainly it's a threat to the PGA Tour," said Spieth.

"I think as a player overall it will benefit in that the changes that have come from the PGA Tour have been modernised in a way that may or may not have come about if it weren't there.

"So for us players on the PGA Tour I think that so far it's been something that has kind of helped the PGA Tour sit and say 'Hey, where can we look to satisfy our membership and potentially make some changes going forward where there's some similarities potentially to a league like that but while maintaining the integrity the PGA Tour has'.

"I can only say from my point of view I think that it's been beneficial to the players to have competition, and I think the Tour would say that they probably feel that they're in a better position going forward by having to sit back and kind of take a look at things and make some changes."

The American is making his first appearance since 2016 at the Sentry Tournament of Champions in Hawaii involving only players who won on the PGA Tour last season.

A total of 38 players will tee it up at Kapalua, where Open champion Collin Morikawa could overtake Jon Rahm as world number one.

"It's still something you got to earn, right?," said Rahm of the looming challenge.

"I'm number one because of how I played in the past, so if I want to stay here I got to keep playing at the level and trying to get better.

"At the end of the day, I focus on myself, right? I try to improve my game and improve my level of golf.

"If I can do that and play the way I know I can play, everything else should take care of itself.

"I'm not thinking constantly 'Oh, he's number two' or 'He's coming for me, I need to do this or that'.

"No, I'm trying to play the best that I can and hopefully win a tournament."