Smith downplays back spasms ahead of India

Steve Smith is confident he will recover from a back complaint in time for next month's Test tour of India.

Smith played the best innings of his T20 career on Saturday night, stroking his way to an unbeaten 125 as his Sydney Sixers thrashed Big Bash rivals the Sydney Thunder at the SCG.

Smith's second consecutive BBL century was all the more impressive given he put his back out in the nets on game day.

The former Test captain had to cut his training session short on Saturday afternoon to rest his back, which was still going into spasms when the Sixers' were in the field.

Smith struggled to run late in the game but was not substituted out.

"I just had some spasming this afternoon," he said post-match.

"I struggle to get upright.

"I can bend (forwards) all right but getting into an extension is not ideal. It probably helped me in my batting, kept me a bit lower.

"It's a bit stiff but hopefully I pull up okay."

Sixers spinner Nathan Lyon missed a second-straight BBL match with knee soreness but Smith does not believe he or his Test teammate are in doubt for the tour of India that begins on February 9.

"I'm pretty certain we'll be all right," he said.

Opening the batting, Smith has averaged 131 across his three innings for the Sixers and has already hit the equal-most sixes of anyone in the BBL this summer.

His recent form at the top of the order comes despite falling out of favour in the Australian T20I set-up and not yet being considered an option to open the batting for his country.

Smith played just one of four games in Australia's T20 World Cup campaign last year.

But the 33-year-old said his recent form had been driven by his love for the game, not a desire to re-assert his status as a multi-format player.

"I just came here to play and enjoy myself and help the Sixers have success," he said.

"In my first three knocks, I've batted nicely in all of them.

"I feel like I'm in a good place at the top of the order.

"It's a place I think most people probably enjoy batting. It's been really enjoyable so far."