Ahead of India’s much-awaited first Day/Night Test against Bangladesh, veteran spinner reckoned that wrist spinners, landing the pink ball with scrambled seam, will be far more difficult for the batsmen to pick than finger spinners.

After defeating the visitors in the white-ball format, Virat & Co. will be taking on B’desh in the historic pink ball Test at the Eden Gardens from Saturday.

"Wrist spinners will have one advantage if you see because it's going to be very difficult to pick the seam (with black stitches) of pink ball," Harbhajan told PTI. India has a wrist spinner in Kuldeep Yadav but Harbhajan avoided talking on selection matters.

"Well, that's the team management's call and I can't comment. But then Bangladesh need to play the Indian pacers on the seamer friendly track before spinners are fully operational," he said, referring to their performance against Mohammed Shami and co in the first Test.

"And also between 3.30 and 4.30 pm, the time of sunset in Kolkata where seamers are known to do maximum damage. But yes we need to figure out more about spinners if we want to play more D/N Tests in future."

He reminded how Kuldeep turned out to be lethal during the 2016 Duleep Trophy, played with the pink ball.

"If you remember Duleep Trophy, no one could effectively read Kuldeep from his wrists. Leg spinners got lot of wickets during that edition," Harbhajan said.

He explained why wrist spinners are more effective.

"When a finger spinner bowls, the ball is released with seam so that there is turn and bounce. When you are bowling the googly, the seam will be scrambled and very difficult to pick," he explained.

However, someone like a Muttiah Muralitharan might just be very effective.

"But there are exceptions like Muttiah Muralitharan, who could have been a killer with the pink ball despite being a finger spinner because unlike other finger spinners, both his off break and doosra were released with scrambled seam," said one of India's greatest spinners.

The pink SG in general will be a challenge for the spinners with the extra lacquer that will be applied to keep its colour intact under lights.