England's selectors face a difficult call over the potential inclusion of Jamie Overton in their T20 World Cup squad after an inconclusive scan left the Surrey allrounder unclear as to the extent of a recent back injury. ESPNcricinfo revealed this month that Overton was in line for a maiden T20I call-up after making significant strides as a short-format allrounder. Rob Key, England's managing director, has been monitoring his progress since his return from injury last summer and Overton said he felt "close" to selection even before Ben Stokes' withdrawal. But he was ruled out of Surrey's County Championship fixture against Kent last week with a back issue, and will not feature against Warwickshire this week after initial scans returned unclear results. He is due for another scan in two weeks' time after a short period of rest, by which time England will have named their provisional squad to meet the ICC's May 1 deadline. England's selection panel - which Key chairs - will meet in the next few days to finalise their 15-man squad, which is likely to double-up as the group that faces Pakistan in four T20Is from May 22-30. There are a few details to iron out, with Ben Duckett in contention to be the spare batter and Tom Hartley likely to get the nod as second spinner ahead of Rehan Ahmed. Jofra Archer is set to be named in the provisional squad and given the chance to prove his fitness against Pakistan, over a year after his most recent international appearance. The uncertainty over Overton's injury may also open the door for Chris Jordan to be recalled. Jordan was left out of the squad that lost 3-2 to West Indies in December but has been a consistent six-hitter in the last 12 months. The identity of England's wicketkeeper will also be up for discussion, with the ICC's new stop-clock and fielding penalties for slow over-rates making it more challenging for Buttler to captain the side while also keeping wicket. Phil Salt took the gloves in the final two T20Is of England's Caribbean tour in December, while Jonny Bairstow is the other alternative. The ECB has not yet indicated publicly whether it will allow England players to stay at the IPL for the knockout stages if their franchises qualify, which would rule them out of the first two Pakistan T20Is. Buttler, who has recently scored two unbeaten hundreds for table-topping Rajasthan Royals, is likely to miss the start of the Pakistan series regardless while on paternity leave. England are expected to name their squad on Tuesday morning. They will have until May 25 - the day of the second T20I against Pakistan - to make changes but will be keen to avoid a repeat of the debacle last year that ensued when Harry Brook was drafted into their 50-over World Cup squad at late notice after his initial omission.