In reply, India were placed at 25/1, trailing by 544 runs at stumps.
"We were expecting a fight-back from England (after the defeat in the last Test)," said Kumar.
"So we expected them to come back stronger. The wicket was good for batsmen and as a bowling unit we did our best.
"Sometimes it happens," he added, referring to the poor performance in comparison with the way India bowled in the first two Tests.
"We were tired and had been in the field for nearly two days. So we just didn't get it right."
After a long time spent in the field, India even resorted to strange tactics post-lunch when M S Dhoni deployed his three medium pacers in one-over spells. It did help produce two wickets wherein only 30 runs were conceded in 13 overs.
"We were tired as I said and it was an easy wicket for the batsmen. So it was hard work. So the captain wanted us to bowl one-over spells and personally I found that easy. That way we didn't really get tired and we also found our rhythm," said Kumar, obviously impressed with the tactic since he picked both wickets in this interim.
However India could have done better had they taken all the chances that had come their way. After Alastair Cook was dropped by Ravindra Jadeja on day one, Shikhar Dhawan dropped Jos Buttler and then Dhoni also missed a stumping chance off the same batsman as he went on to score 85 runs.
"Being a bowler, you expect them to catch those. But we also know they will catch a few, they will drop a few. This happens in cricket and happens with every team. We just have to give them confidence. Overall the catching in this series has been quite good," he said.
"Buttler played a crucial innings. But the pitch was also easy for the batsmen. We tried not giving him room because he was looking to play shots. We were looking to get him out all the time he was attacking the ball and finally we managed to do so," he added.
Last but not the least, Kumar also reserved some praise for India's own debutant Pankaj Singh who went wicket-less in his first outing.
"We are very happy with the way Pankaj bowled in his debut match. He has worked hard and did well, but was unlucky to not get any wickets. That part is not in our control," Kumar signed off.