Taskin Ahmed, who has played more Tests than Mahmud, and Nahid Rana, who bowls much quicker, did not stick to this simple approach. They bowled too short, too wide or too full, giving the batters plenty of freebies. Mahmud simply used the devices available to him - seam, swing, pace and the right lengths - and became the first overseas quick in nearly 15 years to take three wickets in the first session of a Test match against India in India.

"It is obviously great to take Test wickets," Mahmud said. "I took a five-for against Pakistan so it was about trying to be consistent in my effort to contribute to the team. Today's plan was very simple. I tried to shape the ball with the seam up. I kept trying to do it and [it paid off]. After the morning session which we dominated, the wicket got settled. The ball was coming onto the bat nicely. Still, I was getting some movement later on. Maybe tomorrow we can create more chances."

Every wicket Mahmud took on the first day in Chennai was well thought out. He built up a case against each batter, whether over a short or long period. Mahmud got the ball to hoop in slightly overcast conditions and tested both of Rohit Sharma's edges. A skewed edge got Rohit an early boundary before he survived an lbw shout in the fourth over, when the ball ducked in from a slightly shorter length. Then came a subtle outgoing delivery that took his outside edge, well taken by Najmul Hossain Shanto at second slip.

India's No. 3 Shubman Gill, who couldn't get Mahmud away for seven balls, also survived an lbw shout. His dismissal was a lucky one perhaps, when he was caught down the leg side, but it looked like Gill was itching to get off the mark. A batter strangling one down the leg side is often the result of early dot-ball pressure.

Mahmud then had Virat Kohli caught behind chasing an outside-off-stump delivery. The ball before, Kohli had played a confident forward push, but Mahmud stuck to his guns. He got the seam to wobble again and lured Kohli out for a drive.

Shanto gave Mahmud a first spell of seven overs, mainly because of the overcast conditions and how well he was bowling at that time. As he had shown in Rawalpindi, though, Mahmud isn't only about the new ball. He took a wicket shortly into his second spell, getting Rishabh Pant caught behind. This time too, he tested Pant outside the off stump. When he was cut for a boundary, Mahmud dragged the next ball across but moved the line slightly closer to Pant, who edged it to the wicketkeeper.

Mahmud kept creating chances in his later spells too, having R Ashwin edge one between slip and gully, and having Ravindra Jadeja given out lbw before the decision was overturned on review. He got another to nip back into Ashwin but this appeal didn't have a lot of merit.

Bangladesh were certainly not in a dominant position at the end of day one in Chennai, but with the second new ball available, Mahmud felt they could still fight their way back into the contest.

"If we can get early breakthroughs tomorrow, we will be back in the game," he said. "We want to restrict them below 400 runs. It is however a good wicket now. The conditions here are almost the same [as Pakistan], but it is the bowlers' duty to bowl aggressively, or cut down the boundaries, whatever is required.

"We were in a dominating position in the morning but the wicket is very good now. We are all trying to minimise the boundaries. The momentum has shifted today, but we could bring it back with better bowling tomorrow."

Mahmud also has some experience in white-ball cricket, where he has usually bowled with both the new and old ball, but he has gone down the pecking order in recent times, with Tanzim Hasan Sakib playing ahead of him whiile Taskin Ahmed and Mustafizur Rahman are mainstays.

Mahmud's transition into red-ball cricket now means Bangladesh's pace attack is ever-expanding. They have Khaled Ahmed in the Test squad in India. Shoriful Islam, Tanzim and Mustafizur are go-tos in T20Is, while Ebadot Hossain is close to full fitness and could be available from the home Test series against South Africa next month.

Despite their recent uptick, the pace attack remains a work in progress. It seemed like the Bangladesh bowlers took their foot off the gas as the day went on, letting Ashwin and Jadeja build a counterattacking stand. If the pace attack's development is anything to go by, though, they can be expected to come up with better plans on the second morning.