1st Test, Day 2: Michael Clarke, Steve Smith Dominate India on Rain-Hit Day

Australia were 517 for seven at the close on the rain-disrupted second day of the first Test against India at the Adelaide Oval on Wednesday. (Scorecard | Day 2 Highlights)

Skipper Michael Clarke (128) and Steve Smith (162 not out) joined David Warner (145) as century-makers in the Australia innings.

At stumps, Smith was unbeaten on 162 with Mitchell Johnson yet to score.

Smith raised his fifth Test century and saluted his fallen Australia team-mate Phillip Hughes in between frustrating rain delays on the second day of the opening Test against India on Wednesday. 

Smith clipped the first ball after lunch for two to bring up his hundred, touching off more tributes to Hughes who was fatally struck by a bouncer in a domestic game late last month.

He jogged away from the wicket and pointed towards the '408' -- Hughes's Test cap number -- painted on the playing surface and then raised his bat and looked skywards in tribute to the batsman.

Smith then shared another long hug with batting partner Michael Clarke, who was also at the wicket when David Warner reached his century on day one.

The emotion continued when the crowd broke out into applause when the Australian total reached 408.

When rain forced the players from the field for a second time on day two, the home side were 423 for six with Smith unbeaten on 103 and Clarke nearing his 28th Test century on 98.

Clarke returned to the crease at the outset of day two and batted clearly in discomfort, but he provided dependable support for Smith.

Clarke, who needed injections to resume his innings after retiring hurt with a bad back on the opening day, grimaced and yelped in pain as he twisted his torso to play some shots.

His running between the wickets was constrained, but he and Smith kept the scoreboard ticking over with a handful of sweetly-timed boundaries.

The Australian skipper has earned a reputation for courageous displays. Last March he batted on with a fractured left shoulder in an unbeaten 161 to help his team to a 2-1 series victory over South Africa in Cape Town.

Clarke only played in the Adelaide Test after passing a fitness test for recurring hamstring trouble.

Team physio Alex Kountouris said he was struggling with a "significant back injury."

"This is his right lower back. This is his old injury, what he's had in the past. I don't think it's directly related to his hamstring, because it's the other side," Kountouris said before the start of Wednesday's play.

"We believe it's related to his old disc injuries. With that comes a lot of muscle spasms and other things that cause pain."

The morning session took place under cloudy skies with the ground's floodlights switched on.