Martyn did a valuable job for his team

The tourists, who lead the series 1-0, ended a rain-hit third day on 320-5 with Damien Martyn 104 not out.

"The game is on a knife edge. One good ball early tomorrow and we're right back in the game," claimed Dyson.

Martyn was dropped twice on the way to his century but said: "You need some luck in these conditions."

The 32-year-old also made 110 in the first Test at Galle and described them as "the hardest hundreds I've had to get".

He added: "The first was a big one because I hadn't got one for a couple of years. Now it just feels I'm being consistent.

"I've had to fight hard and it's good to be out there batting a long time."

Chaminda Vaas celebrates the wicket of Ricky Ponting

Martyn's century took six hours and 21 minutes, the fourth slowest in history by an Australian in a Test, but he was unconcerned.

"I'm pleased that I can bat for a long time at this level.

"It's great to be able to make runs on the sub-continent. It's one of the frontiers that you like to make runs in. It's very satisfying to make runs against quality spin bowling."

Dyson was satisfied with the efforts of the Sri Lanka bowlers during the truncated day's play despite Australia's strong position.

"I don't think there were too many easy runs given all day. They had to work for their runs - we had to work for our wickets."