Buttler raced to 67 not out before injuring his hamstring against Sri Lanka at Headingley. He returned after retiring hurt but was dismissed for 69 from 49 balls

Wicketkeeper Jos Buttler will miss England's 50-over tri-series in Pakistan next month, with Jordan Cox set to be given another chance to impress in his place.

Buttler, 36, has been ruled out with the hamstring injury suffered while batting in Thursday's second one-day international against Sri Lanka at Headingley.

Coach Brendon McCullum said it is "hard to judge" how long Buttler will be out for and confirmed Cox will take his place for the series against Pakistan and Sri Lanka, which begins on 20 October.

"We know Jos is an incredible athlete, we know he is supremely fit and is an ultra-professional," McCullum said.

"He will do everything he can to be back as soon as possible."

England also tour Australia for white-ball matches in November - where they are considering playing warm-up matches - as they look to add to their six series wins in limited-overs cricket this year and build towards next year's 50-over World Cup.

They will finalise their squads on Monday with the latest batch of central contracts also set to be announced in the coming days.

Durham opener Emilio Gay is in line for a first deal after his debut Test summer, putting him in line to tour South Africa this winter, while Cox, Tom Banton, who scored his first international century on Sunday, and all-rounder Dan Lawrence could also feature.

Contracts held by former captain Ben Stokes and Mark Wood are set to end after their international retirements. Ollie Pope, Zak Crawley, Matthew Potts and Luke Wood are all out of favour and their one-year deals are due to run out.

Spinner Shoaib Bashir is another intriguing name in that category. He played two Tests against New Zealand and was picked in the Test squad to play Pakistan but did not make an XI as England preferred a four-man pace attack.

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In a breakout international summer, Cox impressed by scoring fifties in all three Tests when picked to bat number three against Pakistan. He also hit 76 against Sri Lanka when deputising for Buttler in the third ODI at The Oval on Sunday.

"I thought it was quite a Jos Buttler innings," McCullum said.

"He has done really well domestically for a number of years and has been unlucky with injuries.

"For him to have the type of summer he has had and be in the position he is in, he deserves it.

"He is a phenomenal talent, is very well liked in dressing room as well and seems to be one of those guys who is good at everything he does, which will be incredibly annoying."

England will also make a decision on whether to pick bowler Brydon Carse to tour Pakistan. He has not been selected since being arrested then de-arrested on a night out in Derby in August.

After a police investigation ended without action, he is now subject to a Cricket Regulator investigation and, while he remains available for selection, white-ball captain Harry Brook said last week he needs time away from the international scene.

McCullum, who began the summer as England's coach across the three formats before being sacked from the Test role in July, dismissed any suggestion of regret at the end of the English season.

"I loved coaching all three formats," he said. "Things move on, times change. I am biased but I genuinely think [new Test coach] Stephen Fleming will do an unbelievable job with the red-ball side.

"With the extra bit of time it probably does allow you to drill down on a few aspects you have identified you need to improve or shape things differently to get to where you want to."

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