Former India head coach Ravi Shastri has called upon Shreyas Iyer and Ishan Kishan, who were excluded from the BCCI contracts on Wednesday, to dig deep within themselves and come up stronger, saying `comebacks define the spirit` in the game of cricket.

Earlier, batter Iyer was not part of Ranji Trophy quarterfinal, held on February 23, due to "back spasms". He represents Mumbai in Ranji Trophy.