Ishant's 10th five-wicket haul helped the hosts bowl out Bangladesh for just 106 on the opening day of first pink ball Test in India at the Eden Gardens on Friday.
At stumps, India were 174/3 with a lead of 68 runs. Virat Kohli was unbeaten on 59 while Cheteshwar Pujara also scored a classy 55.
"The important thing is that we have very healthy competition. It's not about individual performance. If you don't have healthy competition and you don't have someone to challenge your place, I don't think you can perform this well," Ishant said after the day's play.
The senior pacer gave Hanuma Vihari's example. Vihari did well in the West Indies but was not included in the home series against South Africa and Bangladesh as India played five bowlers.
"The best example is Hanuma Vihari. He got so many runs in the West Indies, but we needed to play five bowlers in India so he was left out," said Ishant, who returned figures of 5/22.
Asked about the secret behind his success in recent years, Ishant said that he was enjoying his game more now.
"I am enjoying my cricket right now. I used to take more pressure before. Now I think about taking wickets only. I have experience, so seeing the wicket you need to adjust your length. In India, it is easier to perform," he said.
This was Ishant's first fifer at home after 12 years. He said that he wanted to continue his away form here with the same mindset.
"I did not do anything different. We have been playing abroad a lot. So I wanted to continue the form and mindset. I thought if I can take wickets abroad, why not in India," the seamer from Delhi said.
Asked about the feel of the pink ball which has extra lacquer compared to the red ball, Ishant said: "Pink ball is very different to red ball. When we started bowling at normal lengths, the ball was not swinging much. We then figured out the length. We talked about it among ourselves, the three fast bowlers. We started hitting the right lengths after that."
Ishant also said the pitch was two-paced in the beginning but India expected that.
"The pitch was ok. I felt it was two-paced in the beginning. We expected a two-paced wicket like it was in the nets," he said.
Ishant has added a new variety to his bowling, a delivery which comes into the lefthander. Quizzed about that, he said: "I used to bowl outswingers to left handers before. I needed to add some variation as your game only improves if you do that and can be confident to implement that in the match. So in this match, Imrul Kayes' dismissal was that ball and the two bowled dismissals too."
Ishant is not a part of India's limited overs side now. He said he feels bad but at this stage of his career, he does not dwell on that.
"It feels bad, but I am at that stage of my life where I don't think about these things. They don't affect me. I am 31 now. I just want to play and that way automatically you do well," he said.