Kevin Pietersen reignited his long-running feud with Sir Alastair Cook over his former England team-mate's criticisms of Jacob Bethell being at the Indian Premier League.
Bethell has been unused by Royal Challengers Bengaluru and Cook urged the youngster to return to Warwickshire to play county cricket instead of "sitting on his a*** at the IPL not doing anything."
Pietersen, who was banished from the England set-up when Cook was captain after the 2013-14 Ashes, argued the former left-handed opener's lack of IPL experience renders his judgement irrelevant.
"Alastair Cook has absolutely NO IDEA what it's like to be in the IPL," Pietersen wrote on X. "What it's like to always be around the best players in the world.
"So his opinion on Jacob Bethell doesn't matter at all. Stay in India, Jacob. I know, even though you're not playing, you're learning and will be a way better player."
Pietersen later added in a separate X post: "If county cricket was as strong as it was in the late 90s and early 2000s, I'd also want Bethell back playing it now. But, it's NOT! It'll benefit England more by him being in India and he's already shown that."
Bethell has had a breakout past few months to establish himself in England's top-order across all three formats following hundreds in the Ashes in Sydney and the T20 World Cup semi-final against India.
While he has been sat on the sidelines for all of RCB's first six matches, Bethell, who is earning around ÂŁ250,000 from his deal, defended being at the IPL rather than at Edgbaston.
"I firmly believe that this is the thing for me to be doing right now,"
"I feel better now than I was a month ago after the World Cup, just from getting time around the guys over here and the pure standard of cricket in India and the IPL.
"Every nets session, you've got hundreds of eyes on you, be it your coaches or the other players who are also looking at you, going, 'Is this guy good? Is he not?' You've got the people in the crowd with their phones on. You get exposed to a lot of stuff."
Bethell's 154 from number three in January at the end of England's miserable tour of Australia means he should be in the XI for the first Test of the summer against New Zealand, starting on June 4 at Lord's.
He has been linked with moving up to open, where he has batted in white-ball cricket, if England discard Zak Crawley, which could lead to the in-form James Rew being selected in the middle-order.
Bethell admitted he would prefer to stay at first drop but would do whatever he is told, highlighting Joe Root being moved to opener to accommodate a returning Pietersen ahead of the 2013 Ashes.
"I'd love to stay at three, if it's up to me. I really like the position," Bethell added. "I don't think there's a massive difference between three and the top.
"Someone like Rooty had to start opening the batting and then kind of sit back down into number four. So if that's what they want me to do, I'd be more than happy to do it.
"But, I like three and I'd love to cement that spot as mine if possible."
England opener recently to play for Nottinghamshire and shore up his Test spot, but it seems a long shot that Bethell will seek an early exit.
RCB are well placed in the standings and an agreement is already in place with the England and Wales Cricket Board over player availability.
Cook feels Bethell showed Down Under that he could answer England's problems at opener, where Crawley looks certain to make way, but is worried by his lack of cricket.
"For that top order batting, the way he played at Sydney, against that attack, in those conditions - I've looked at a player there and I'm certain this bloke can open. If he can bat three, he can open," Cook said on the Stick to Cricket podcast.
"(But) it's not ideal, is it? Bethell shouldn't really be it, because he's not opening. He's sitting on his a*** at the IPL not doing anything. Ideally he could come back and open for Warwickshire to help England."
But Bethell says even the net sessions outside of matches have pressure in India.
"You might not get the amount of time in the middle as [you do] in County Championship playing four rounds of that. But I think in terms of the ability to actually just continue doing what you want to do when there are loads of eyes on you, is really important for me personally going forward.
"Also, it's been scheduled in now where we've had practice matches when we're not playing. I know that's not going to be the same as an actual competitive game, but we're getting time out in the middle from that because it feels like the whole squad's pulling together to try.
"They know it's going to be a team effort, a squad effort to win the trophy again. And Coxsy (England international Jordan Cox) as well is not being left just to ponder about what's happening on the sideline.
Bethell's sublime unbeaten 142 at the Sydney Cricket Ground was one of the few highlights during England's 4-1 Ashes defeat over the winter.
He was hailed as "the future of England cricket" by Cook following his performance in Sydney, which was only his sixth Test, and there has been talk over whether Bethell should move up to open the batting, which would also create a spot for Somerset wicketkeeper-batter Rew to come into the team.
Bethell says his performances for England are what he "pretty much believed in", despite question marks about him not hitting a century in professional cricket prior to his Sydney heroics.
"There was obviously a lot of talk around the no first-class hundred or whatever, but I never paid that too much attention.
"I felt like I've always played better against better opposition, and that's shown a bit in terms of, I like playing against great teams and taking on good bowlers.
"You can look at the three hundreds (his first in both ODI and T20 internationals) and go, 'it's been great'. But there's been some lean patches in there as well.
"I didn't have the greatest English summer last year and then topped it off with a hundred, and then some low scores in New Zealand prior to the Ashes was actually a bit out of touch going into that series.
"You can look at it from the outside and say it's all smooth sailing, but it's been nice to actually go up and down and actually just learn to deal with that through spending a year on the road pretty much.
"It's been great to have those standout moments, but all it does is make me hungry for a lot more."
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