Eoin Morgan believes it is "naive" to think that England could parachute Jofra Archer into a World Cup match if they were "desperate", as Archer continues his comeback from an elbow stress fracture.
Archer is due to arrive in India next week, linking up with England's squad in Mumbai, and is their only designated travelling reserve for the tournament. He bowled in England training during their ODI series against New Zealand last month and has recently been bowling at Hove as part of his rehabilitation.
Archer will be on standby in the event of an injury to one of England's six frontline seamers. Morgan, the ex-England captain, said he would have to be managed "extremely well," having played his most recent competitive game in the IPL four months ago and with no opportunity to prove his fitness in a match scenario.
Asked about the potential value of Archer's bowling on Indian pitches, Morgan said: "Right here and now, I don't know - because he's not played, and we don't know what he's capable of. Obviously, the feedback about when he's trained with the team has been that he's back bowling beautifully, but you would like to see that in a game.
"You would like to see that in a continuous performance. You would have to manage that extremely well because, given the injury issue that he's had in recent times, I think it would be naive of anybody to think [you should] just chuck him in whenever you can because we're either desperate or feel that you are an option."
Jos Buttler, Morgan's successor, said there would be "a conversation" around Archer's readiness in the event that a seamer went down injured. "He's coming out soon," Buttler said. "The plan is obviously to finish off the rehab stages of coming back from his injury, so he'll join up with the team soon.
"He's coming in as a reserve, so he's not in the squad. And he's continuing to build up and rehab, and that's a great place for him to be able to do that, in and around the squad here. Obviously, if he builds up and everything then, should the worst-case [scenario] happen, it's a conversation."
Morgan, speaking as an ICC Men's World Cup ambassador, played down the likelihood of Archer featuring soon. "For him to play there needs to be quite a significant injury," he said. "We're only a week into the tournament, so it would need to be a six-week injury to a bowler."