Mitchell Swepson has frankly admitted doubts crept into his mind during his 514-ball wait for a third Test wicket.

Swepson justified his selection as Australia's second spinner in the team's series-opening win over Sri Lanka, taking five wickets for the match in Galle.

But it wasn't before a harsh introduction to Test cricket.

The legspinner took 2-266 across his maiden two Tests on flat Pakistan wickets, including a barren 81.4 overs without a wicket to end the series.

"I'm not going to lie, it plays on your mind," Swepson said.

"It definitely creeps in. 'Why aren't I taking wickets? What am I doing wrong here?'

"At the same time in Pakistan I know it was about trying to stay effective. A big focus of ours was trying to control the tempo of the game.

"That was what I had to bring my mind back to if the results weren't at my end."

Swepson is expected to hold his spot as Nathan Lyon's spin partner for the final Test in Galle starting Friday, holding out a fit-again Jon Holland.

His success in Sri Lanka has been a long time in the making.

The Queenslander went on an academy tour to India in 2015, and was also a member of Australia's Test squad for the 2017 Test series in that country.

He has since worked on developing his bowling for sub-continent conditions, well aware that is where his chance would come.

Swepson has tended to bowl with a "squarer" seam in Sri Lanka than he does Australia, forgoing some drift but picking up more natural variation in his spin.

"You've got to adapt to the surface," Swepson said.

"Over here I've found that different paces react differently off the wickets.

"It's a matter of flight, it's a matter what shape you put on the ball, the angle of the seam.

"I found it quite effective in my first spell bowling with a squarer seam, not as over the top of the ball.

"Some were skidding past the left-hander's edge, some were ripping into his gloves."

Swepson is happy to push the cause for Australia playing two spinners back home this summer, having not picked a wrist-spinner at home since Brad Hogg in 2007-08.

But the 28-year-old is more realistically accepting his next chance will come in India in February.

"I've obviously got one eye on India. That's definitely a goal of mine. And a goal of this group is to get a series win over there," he said.

"I love bowling with Gaz (Lyon) ... It's great having an offspinner and a legspinner working in tandem (spinning it different ways).

"Again, biased opinion of mine. But I think it's something we don't see enough of in cricket."