With several frontline batsmen, including regular skipper Virat Kohli, either resting or recuperating, India picked a depleted squad with Ajinkya Rahane as the stand-in captain for the opening Test in Kanpur.

Iyer grabbed the opportunity with both hands and followed his first-innings 105 with an equally crucial 65 on Sunday to put India in the box seat.

Kohli is set to return to the squad for the Mumbai Test and batting coach Vikram Rathour said they were not in a hurry to finalise the playing XI yet.

"The captain coming back in, that will happen in the next game," Rathour said after the penultimate day's play at Kanpur's Green Park Stadium on Sunday.

"We'll get to that point when we reach Mumbai. At this point, we want to focus on this game. There's still a way to go and there's a game to be won."

Rathour was effusive in his praise for Iyer, though.

"It's always exciting to see a debutant come in and score a hundred. It's very special, but I think he played even better in the second innings."

"He is a very confident young guy who uses his feet well and plays spin bowling really well."

Calls have grown to drop either Rahane or Cheteshwar Pujara, both of whom have been short of runs, to accommodate Iyer.

"I understand both are going through lean phases," Rathour said of India's senior batsmen.

"But they've played very important knocks for us in the past. We're pretty sure they'd come back and play more such knocks for the team."

For Iyer, the most satisfying thing would be to see India go 1-0 up in the series.

"In the end, we have to win the match, and that would be the most important thing for me," the 26-year-old said after becoming the first Indian batter to smash a hundred and a fifty on Test debut.

Australian Associated Press