London - England coach Trevor Bayliss has accepted "tough decisions" will need to be made when the selectors pick the Test squad for the upcoming tour of Bangladesh and India.
The most pressing problem that England face following Sunday's 2-2 series draw at home to Pakistan concerns their top order batting.
While England captain Alastair Cook and number three Joe Root scored a combined 935 runs at an average of 66.78 over the four Tests, the rest of the top five - Alex Hales, James Vince and Gary Ballance -- managed 498 runs at 22.63 between them.
Bayliss's preference is to make sure players have time to prove themselves, but following England's 10-wicket loss at The Oval on Sunday, he made it clear that his patience with England's underperforming specialist batsmen was not limitless.
"They've definitely had a decent run at it," said Bayliss.
"We've probably got around a month before we get together and discuss the next Test series, so there will be some tough decisions to be made," the Australian added.
Hales has yet to score a century in 11 Tests and has a meagre average of 27.
At The Oval, he managed just 18 runs in the match, dropped a routine catch and annoyed the England management by getting himself fined after confronting the third umpire about his first-innings dismissal to a controversial low catch.
However, no one in county cricket has yet made an overwhelming case to take over one of England's problem batting positions.
"There doesn't seem to be anyone crying out to be selected above anyone else," added Bayliss.
"There's a number of guys we've seen score some runs earlier this season, under a bit of scrutiny when their names are mentioned about the possibility of getting into the team.
"Some of them have dropped off."
Bayliss added: "I think I heard Cookie say the two or three guys we've got in the team have been very good players over the last two or three years, experienced players at county level, and they have found it tough to jump up to this level.
"They have shown bits and pieces, but I think it just proves that the jump between first-class cricket and Test cricket is a big one."
With Bayliss also coaching England's one-day side he has few chances to watch any of the contenders himself by attending county fixtures.
"Certainly, I'll be trying to get there when I can," he said.
"There might be a chance in the next few days, but you've got to be lucky enough that whoever you are going to watch is actually batting or bowling on that day," he said.
Meanwhile England are due to announced on Tuesday their squad for a five-match one-day international series against Pakistan starting next week.
Few changes are expected from the side that defeated Sri Lanka earlier in the season but the Durham duo of all-rounder Ben Stokes and paceman Mark Wood could return from injury.
Stokes has been sidelined with knee and calf injuries this season while Wood has undergone two ankle operations since last playing for England in a Test against Pakistan in Dubai in October.
Eoin Morgan, England's ODI captain and wicket-keeper Jos Buttler have been out of action recently with hand injuries, but they are both understood to be fit for selection.