England's Jos Buttler could yet face action from world cricket's governing body for the message he writes on the top of every one of his bat handles.

Buttler produced a man-of-the-match innings of 80 not out as England beat Pakistan by an innings and 55 runs inside three days at Headingley to win the second Test and level the two-match series at 1-1.

During a break in play, television cameras highlighted the words "F*** it" written on the top of his bat handle.

QUICK SINGLE Buttler's bat message attracts attention

Buttler, who explained he marks the top of all his bats in this way, said it's a way of reminding himself not to get too wrapped up in the pressure of top-level sport.

"I think it's just something that reminds me of what my best mindset is – when I'm playing cricket, and probably in life as well," he said.

"It puts cricket in perspective. When you nick off, does it really matter?"

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"It's just a good reminder when I'm in the middle, when I'm questioning myself, and it brings me back to a good place."

But the International Cricket Council might take a different view.

The ICC's clothing and equipment rules and regulations state: "Players and team officials shall not be permitted to wear, display or otherwise convey messages through arm bands or other items affixed to clothing or equipment unless approved in advance by both the player or team official's board and the ICC Cricket Operations Department ... the ICC shall have the final say in determining whether any such message is approved."

It's hard to believe the ICC would have granted prior approval for the words on Buttler's bat and there is precedent for them taking action against players for words or logos worn on the field.

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In 2014, England's Moeen Ali was banned from wearing wristbands that read "Save Gaza" and "Free Palestine", the ICC saying that players are not permitted to display "messages that relate to political, religious or racial activities or causes during an international match".

And in 2013, Pakistan were found to have breached the ICC's rules regarding commercial and sponsors logos on their playing strip.

Whether the ICC will take action in the Buttler case will depend on whether the umpires decide to charge Buttler and, in turn, how match referee Jeff Crowe responds.

Buttler was recalled for the Pakistan series after 18 months out of the Test side by England's new national selector, Ed Smith.

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Smith justified his decision on the basis of Buttler's form in the Indian Premier League, where he cemented his reputation as one of the world's leading white-ball batsmen.

Buttler responded to Smith's backing with two fifties in as many Tests, albeit the first coming in a nine-wicket defeat by Pakistan at Lord's.

And after 20 matches in an up-and-down Test career, Buttler believes he is now learning to trust his instincts rather than worry about how others think he should play – a message reinforced by the words on his bat handle.

"If anything my mentality has been quite similar to my first few Tests; not worrying about external factors, just trying to play the game, trusting myself," he said.

"The big difference is experience.

"I used to think you could either do it or you can't.

"But now I understand how valuable experience is, and maturity, to help you to deal with not only the on-field stuff but what goes on around it."