Sri Lanka ended the first day of the Colombo Test against Zimbabwe 63 runs adrift, with only three first-innings wickets in hand, and their own lead spinner has sounded out a warning: batting fourth on this track "won't be easy".

Khettarama is not a venue where Tests are often played - the most recent one was four years ago. As both sides attempt to read an unfamiliar surface, perhaps Rangana Herath's assessments should be given greater weight than those of anybody else. Not only did he claim five wickets in the first innings, Herath had also taken 12 wickets against Bangladesh in that 2013 Test.

So, if Sri Lanka do not come charging back into the game on day three, they may leave themselves with too much to do in the final innings.

"If we can get to 350 or 400 - even get a first-innings lead of about 50, that would be good," Herath said. "But if we can't manage that, we have to get them out cheaply in the second innings. Batting fourth on this track won't be easy. We've got two spinners in the XI, so I think we'll be able to get them out for an average score or below. But right now, I think we should have been in a better position than this."

After Herath had wrapped up a 30th five-wicket haul in the morning, Zimbabwe captain Graeme Cremer took the lead spinners' baton, and finished the day with figures of 3 for 100 from 30 overs. All three of his victims - Kusal Mendis, Dinesh Chandimal and Niroshan Dickwella - fell to big-turning legbreaks.

"If you take yesterday and today, the pitch is drier now than it was," Herath said as he explained the increased purchase for the spinners. "I think that's the nature of the surface - that will be there tomorrow and the day after. The next three days will be good for the spinners, I think.

"We got a good start, but after that Cremer bowled really well. The balls to get Kusal and Chandimal were very good balls. When you get those kinds of deliveries, the chances of getting out are high."

Sri Lanka's plight was also made more difficult by the hamstring injury picked up by Asela Gunaratne, while fielding in the morning. He came in at No. 8 in the batting order, instead of No. 6 or 7 as he usually might, and was clearly struggling to run between the wickets. Gunaratne had claimed two wickets in the first innings, but Sri Lanka's attack may be weakened in the second, Herath said.

"With the state his hamstring is in, I don't think Asela will be able to bowl or field tomorrow. We are also trying to keep him fit for the India tour that's coming up soon. If he is unable to bowl, it's me, Dilruwan Perera and the two quicks who are left in the attack. Kusal Mendis has also taken a wicket in a Test in Zimbabwe, so he might be an option for the captain as well."

That Sri Lanka even find themselves in such a difficult position may also be testament to particular troubles the team has faced in 2017. They had taken large leads into the second innings in each of the Tests they played in Zimbabwe last year, but have since lost four of their last five matches, not to mention a host of ODIs. Despite those results, Herath believed there was quality in the side.

"It's not like we don't have the talent. We do. But we haven't been able to showcase those skills over a long period of time. After the Australia tour last year, we lost the South Africa series. Later, we lost to Bangladesh. It's that lack of consistent performance. We've got a young team with only three or four experienced hands, and we can't expect the older players to do everything. We have to give the young players experience, and they should also know how to make use of those opportunities."

Andrew Fidel Fernando is ESPNcricinfo's Sri Lanka correspondent. @andrewffernando