England captain Alastair Cook has admitted that his side have failed to adequately progress over the last 12 months.
England were humiliated on their way to a series whitewash by India, losing the final Test in Chennai by an innings and 75 runs to seal a 4-0 defeat.
The team have now suffered a record-equalling eight Test defeats this year, and Cook acknowledged that they were not good enough against India.
Asked whether his side had stagnated over the past year, Cook told Sky Sports News: "It's a fair shout. You can say whatever you want now, if I turn around and slag everyone off and use emotive language, you're not doing your job. When you lose games of cricket, you get criticised and you have to take it on the chin. All the guys gave it their all, we just weren't good enough.
"That's the culmination of the pressure being built up on us over a long period of time and a bit of mental tiredness. People will look at that and say it's an excuse, but we haven't been good enough in these conditions. I said at the beginning of the series it's vitally important that we stayed in the contest for as long as we can, because we've seen in previous tours of India that once they get ahead of you it's very hard to bounce back. It's very hard to stop that momentum.
"We've been in games, we've had good fortune in winning four out of the five tosses and we haven't been good enough to take those opportunities and stay with them. Sometimes you have to hold your hands up and say you're not good enough in these conditions and we have to try and improve when we come back here."
Cook also insisted that he will take his time when making a decision over his future amid calls for him to step down as captain.
