The bad news for England selectors came after they had dropped out-of-form opener Jason Roy from the squad for the tournament in Australia beginning next month.
Bairstow was initially included in the selection but the England and Wales Cricket Board later said he had been ruled out of the rest of the summer and the T20 World Cup after suffering a lower limb injury in a freak accident while playing golf on Friday.
Bairstow is understood to have slipped while approaching a tee box during a round at Pannal Golf Club near Harrogate, an innocuous incident but one that has left him requiring surgery and facing several months on the sidelines.
The 32-year-old will be badly missed by his country, having hit a career-best run of form in the Test arena and having been drafted in for the key opener's role in Australia alongside captain Jos Buttler.
Those plans will now require hasty revision, though a reprieve for Roy appears unlikely.Â
Instead, there is a real chance for his Surrey and Oval Invincibles teammate Will Jacks.
Roy has been an integral part of England's white-ball squad and his explosive batting at the top of the order had embodied the team's aggressive approach as they won their maiden 50-overs World Cup title in 2019.
But the 32-year-old has struggled for runs this summer and has hit only 76 runs in total in his last six Twenty20 Internationals.
It made his position untenable for the World Cup and the preceding seven-match Twenty20 series in Pakistan.
Fit-again seamers Chris Woakes and Mark Wood, both of whom last played for England during the Test tour of the West Indies in March, have recovered from their respective injuries to be in both squads.
England's squad includes Chris Jordan (finger) and Liam Livingstone (ankle) who will skip the Pakistan tour to continue their rehabilitation, the ECB said on Friday.
Captain Jos Buttler, who is recovering from a calf injury, will tour Pakistan but will be available to play only in the later stages of the series.
"In Buttler's absence, Moeen Ali will captain the side," the ECB said.
Jordan Cox, Tom Helm, Will Jacks, Olly Stone and Luke Wood are the five uncapped players named in the England squad for the Pakistan series which begins on September 20 in Karachi.
Former champions England begin their Twenty20 World Cup campaign against Afghanistan on October 22 in Perth.
England T20 World Cup squad
Jos Buttler (captain), Moeen Ali, Harry Brook, Sam Curran, Chris Jordan, Liam Livingstone, Dawid Malan, Adil Rashid, Phil Salt, Ben Stokes, Reece Topley, David Willey, Chris Woakes, Mark Wood
Reserves: Liam Dawson, Richard Gleeson, Tymal Mills
England's Pakistan tour squad
Jos Buttler (cptain), Moeen Ali, Harry Brook, Jordan Cox, Sam Curran, Ben Duckett, Liam Dawson, Richard Gleeson, Tom Helm, Will Jacks, Dawid Malan, Adil Rashid, Phil Salt, Olly Stone, Reece Topley, David Willey, Chris Woakes, Luke Wood, Mark Wood.
27°C