Australia's Travis Head plays a shot during day one of the first test cricket match between Sri Lanka and Australia in Galle, Sri Lanka.

Australia's Travis Head, right, bumps fists with Usman Khawaja after hitting a four runs during day one of the first test cricket match between Sri Lanka and Australia in Galle, Sri Lanka.

Australia's Travis Head plays a shot during day one of the first test cricket match between Sri Lanka and Australia in Galle, Sri Lanka.

Australia's Travis Head celebrates his fifty runs during day one of the first test cricket match between Sri Lanka and Australia in Galle, Sri Lanka.

Australia's Usman Khawaja plays a shot as Sri Lanka's Kusal Mendis watches during day one of the first test cricket match between Sri Lanka and Australia in Galle, Sri Lanka.

Australia's Travis Head leaves the ground after losing his wicket during day one of the first test cricket match between Sri Lanka and Australia in Galle, Sri Lanka.

Australia's Usman Khawaja celebrates his fifty runs during day one of the first test cricket match between Sri Lanka and Australia in Galle, Sri Lanka.

Australia's Marnus Labuschagne leaves the ground after losing his wicket during day one of the first test cricket match between Sri Lanka and Australia in Galle, Sri Lanka.

Australia's Usman Khawaja plays a shot during day one of the first test cricket match between Sri Lanka and Australia in Galle, Sri Lanka.

Australia's Steven Smith acknowledges the crowd after completing ten thousand runs during day one of the first test cricket match between Sri Lanka and Australia in Galle, Sri Lanka.

Australia's Steven Smith celebrates his fifty runs during day one of the first test cricket match between Sri Lanka and Australia in Galle, Sri Lanka.

Australia's Steven Smith plays a shot during day one of the first test cricket match between Sri Lanka and Australia in Galle, Sri Lanka.

Australia's Usman Khawaja celebrates his century as Steven Smith watches during day one of the first test cricket match between Sri Lanka and Australia in Galle, Sri Lanka.

Australia's Usman Khawaja and Steven Smith run between the wickets during day one of the first test cricket match between Sri Lanka and Australia in Galle, Sri Lanka.

Australia's Steven Smith celebrates his century during day one of the first test cricket match between Sri Lanka and Australia in Galle, Sri Lanka.

Australia's Steven Smith runs back to pavilion as the play interrupted by rain during day one of the first test cricket match between Sri Lanka and Australia in Galle, Sri Lanka.