There are four Irish players in the field.
Rory McIlroy says he'll have to play percentage golf if he's to win the Masters this week.
The first major of the year starts at Augusta today, with four Irish players in the field - McIlroy, Padraig Harrington, Shane Lowry and Seamus Power.
Harrington is the first of them to tee off after 1.30 - the start time has been pushed back by half an hour due to thunderstorms.
It means Lowry begins his challenge just after 3.30pm, Power is out just before 6, and McIlroy is in the final group shortly after 7.30.
Five time Masters champion Tiger Woods has decided to play, 14 months after being involved in a serious car accident.
McIlroy is bidding to become only the sixth player to win the career Grand Slam.

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