Jordan Spieth may have to reconsider his options for Monday after being surprised by play-off news

Jordan Spieth has admitted he was unaware of the new play-off format that has been introduced for the US Open ahead of this year's tournament at Shinnecock Hills.

The US Open used to be decided by an 18-hole play-off on the Monday, but that was changed in February with the announcement that it will now be a two-hole aggregate play-off if two or more players finish level after 72 holes.

If competitors are still tied after two holes they will move to sudden death.

The new format was also introduced by the USGA for the US Women's Open, the US Senior Open and US Senior Women's Open, but the change obviously passed Spieth by, as he arrived at Shinnecock Hills having already looked at the weather forecast for next Monday.

"It's the first I've heard of that being an option," said Spieth at his press conference on Tuesday when asked for his thoughts on the two-hole play-off.

"It's still 18 holes, right? Oh, it is two. I didn't even know.

"Two on Sunday. I guess strategy changes a little from an entire round, but I honestly had no idea that it even changed.

"I was even looking at a weather forecast for Monday, thinking, you know, what's it look like if you happen to work your way into a play-off? So shows you what I know."

World No 2 Justin Thomas was grateful that the new format had been pointed out to Spieth as he was also in the dark about the change.

"I just read about it at lunch," he said later. "I saw about three people say he didn't know. I'm like well, I'm glad I read this because I didn't know either.

"I think it's good for the US Open and USGA. You're going to have a lot more people out here on Sunday than on Monday, I would think. If I have a chance to win the US Open, I don't care if it's a two-hole play-off or a 72-hole tournament. I'll take a play-off right now."

Spieth has been practising at Shinnecock Hills this week

Spieth will be bidding to win his second US Open title - and fourth major in total - this week at a course he has described as a "spectacular design".

"I enjoy the fact that you're hitting off different slopes," said Spieth, whose previous US Open success came in 2015 at Chambers Bay.

"You have to work. You have to play in the wind. You have to work certain ball flights to hold greens. You can't get away with one ball flight all the time.

"You kind of have to manoeuvre it around off different slopes and winds. It just requires more of an artistic approach. You have three or four different blind tee shots where you've just got to step up and really trust what you're hitting at.

"The fairways aren't necessarily narrow. They'll probably play narrower as the week goes on and as it firms up. So you have to get smaller and smaller targets and not look at what looks like a wide fairway that plays effectively narrow and just be really, really smart about picking apart the golf course. It makes you think a lot."

Meanwhile, Masters champion Patrick Reed has arrived at Shinnecock Hills with his confidence high and is relishing the chance to win back-to-back majors.

Patrick Reed is full of self-belief following his Masters success

"To be able to win the first one of the year and to become Masters champion, it feels great. I feel like it's just made me more hungry to go out, work harder, and try to succeed even more," he said.

"It definitely gives me a little more confidence and gives me that self-belief as well as comfort level that whatever comes down Sunday, if we have a chance to win the golf tournament, I've done it before. So I'm able to kind of build on those experiences from the last major and hopefully be able to apply them this week.

"This golf course is unbelievable. Ever since I showed up and I got on property, I've loved it ever since. I'm just looking forward to the week and can't wait to get started."