Taking his time to get into the groove and punishing good deliveries were the hallmark of Mayank Agarwal's century on the first two days of the ongoing Test against New Zealand in Mumbai, Sachin Tendulkar has said.

Tendulkar was also impressed by the other opener, Shubman Gill, saying the youngster has the required technique and temperament to bat at any position in Tests but he needs to convert those starts into big knocks.

"There was moisture beneath the surface. Mayank took some time to get into the groove and once he was in the groove, he capitalised by putting pressure on spinners," Tendulkar told PTI. "The hallmark of Mayank's innings was that he was able to punish good deliveries too. When a bowler knows a batter can punish your good deliveries, then there is an element of doubt in him.

"What if the batter steps out and hits you and all those things go in bowler's head and disturb his rhythm."

Gill scored 52 and 1 in the Kanpur Test and was bowled by Kyle Jamieson both times. In Mumbai, he looked unperturbed on 44 before he got out to left-arm spinner Ajaz Patel, who finished with a historic 10 for 119.

So does Tendulkar believe that Gill has the technique to do well in South Africa if he bats in middle order?

"When it comes to technique, different surfaces will test you differently. I think Shubman has an advantage as he played a very crucial innings (91) in Brisbane where we won the Test match," Tendulkar said. "He has had the experience of playing on hard and bouncy tracks and I felt that he looked pretty comfortable. So, I don't think there is any technical issue as such."

But does staying "beside the line of the ball" become more advantageous on these surfaces for a batter?

"When he was playing the new ball [in Australia], I think he was behind the line and when the ball got old, he was marginally beside the line as he got to know how much the ball was swinging, how the field is set," Tendulkar explained. "Accordingly, you decide whether you need to be behind the line to play on the on-side or stay beside the line and hit on the off side."

However, Tendulkar wants Gill to convert his starts and is confident that he will do that consistently sooner than later.

"Shubman has started well and shown a lot of promise. The way he builds his innings, he has been good so far. Just that he needs to go further and convert those 40s into big scores."

He doesn't want Gill to take too much stress about three-figure marks.

"Once you get into that squad, it is about how hungry you are for bigger scores which I am sure he is. He needs to just convert those starts and not lose concentration. Both in Kanpur and Mumbai, he got a good deliveries. He is on a learning curve and will definitely take lessons."

Tendulkar was all praise for Shreyas Iyer as well, who impressed on his debut in Kanpur with scores of 105 and 65.

"I thought Shreyas was fantastic and made most of the opportunities he got, at one stage the scoreboard wasn't looking that good and he came up with a gem of an innings and resulted in India almost winning the Test. Both his knocks were important," he said. "I am sure anxiety levels were there but it helped that he had made his T20 debut quite some time ago and these kinds of things ease up your pressure and it allows you to play your natural game.

"Early on, he must have felt nerves and once he connected, he must have felt more confident."