Century-maker Justin Langer expects the Gabba wicket to be even more difficult to bat on when Australia resumes at 2-262 in the first Test against India.

Langer struck 115 not out in a six-hour knock on the rain-affected opening day of the four-Test series.

With recent showers leaving the Gabba wicket green and well grassed, India opted to bowl first in seam-friendly conditions under overcast skies.

The left-handed Langer said the conditions were among the hardest he has confronted in his 11-season Test career.

But he believed batting would be even more testing on day two as the pitch firmed.

"It seamed around a lot all day," he said.

"I think it's going to get tougher to bat on.

"I think as the day wore on the wicket got a bit harder and faster and got tougher to bat on."

Langer's 16th Test century included 16 boundaries, 10 of which came after he nicked and nudged his way to 50.

On passing the half-century he moved into a far higher gear, reeling off his next 50 from only 47 balls.

Brought to you by AAP © 2024 AAP