Steve Smith had to wait 17 months for his 33rd Test century. A key change three years ago may explain why

In 2021, batting in cricket became significantly harder, according to Steve Smith.

Why?

That year, Kookaburra balls were changed. A plastic lining was placed under the seam which helped the ball stand up and an extra layer of lacquer was placed on the ball.

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The result? More swing, seam and a ball that will stay harder for longer.

The other result? More fortune for the bowlers, less for the batters.

So why is this relevant for Steve Smith?

At the Gabba in the third Test against India, the champion batter ended a 17-month wait for his 33rd century.

He'd copped criticism for his form slump, and the relief was plain to see.

He's not the only talented batter who's had lean patches in recent years. Virat Kohli is one. Another is his teammate Marnus Labuschagne.

Smith, who spent time as an opener last summer, made sure to pay tribute to his top three after his ton.

The fact Usman Khawaja, Nathan McSweeney and Marnus Labuschagne all faced 54, 49 and 55 balls each wasn't lost on him and he believes the changes made three years ago have played a major role in how batters should be judged in the modern era.

"I think since 2021 when they changed the Kookaburra ball, batting has got more difficult particularly when at the same time wickets have got greener so it's kind of like the perfect storm coming together," he told media on Sunday evening.

"I think particularly the first 35 overs of an innings are very challenging at the moment with the significant seam movement but the ball stays hard so if you get through that period and you've got some guys like Travis (Head), Marshy (Mitch Marsh) and Alex (Carey) coming in the ball still bounces off the bat a lot harder than it used to.

"I think previously when you got into those positions when the ball gets a bit softer you'll see catches in front of the wicket and things like that and it'd be a bit more difficult to score.

"But the ball's definitely staying harder, so I think the last three years have probably been the hardest that I've experienced in my career batting-wise in terms of the amount of movement that's being generated.

"I think you can see that in the way scores have come down – bowling averages have come down and batting averages have come down.

"If you look back five years ago you're seeing consistent 400, 500s being scored in the first innings, if you put a three in front of it these days you're usually in a pretty strong position so you know you've got to think about that as well when you're thinking about play. Sometimes if you don't get a hundred, it's not the end of the world.

"A good 60 or good 30 at times can be really crucial and match-winning for the team, that's the way I'm seeing things at the moment and if you get a big score you're going to need some luck to do it and you're going to have to play really well."

Smith's comments come after his teammate Usman Khawaja discussed the change prior to the India series starting.

The opener described the seam difference as "the biggest change in cricket for a long time".

"That's why a wobble seam is so prevalent now, everyone just wants to bowl wobble seam when it's not swinging because there's massive seams on them now," he said on The Grade Cricketer.

"That wasn't around back in the day, the old Kookaburra turf seam was so small, it didn't get as much nip, you had to try and swing it and then when it didn't you had to try and reverse it ... the batsmen haven't got worse, it's just got harder to score runs."