An unbeaten 41 from Moeen Ali and a much improved bowling performance helped England overcome a disastrous start against Afghanistan and record their second win of the tournament.
England's victory means they sit second in Group 1 and Eoin Morgan's side are now certain to reach the semi finals if they can overcome Sri Lanka on Saturday and the West Indies beat South Africa on Friday.
After their thrilling record run chase enabled them to beat South Africa in their last fixture, England's batsmen would have been confident when their skipper opted to open the batting after winning the toss. But after a slow and steady start an all too familiar batting collapse reared its ugly head.
At 42-1, the 2010 champions might've looked to be building a relatively solid platform but three wickets in one over (James Vince, Morgan and Joe Root) sent England in a tailspin and they stumbled to 85-7, with Mohammad Nabi (2-17 from 4) the main dangerman.
Ali eventually wrestled back a measure of control for England and the bowlers clung to it. Ali's 41 came from 33 balls and helped England to 142-7.
The all-rounder was ably supported by opening bowler David Willey, who scored 20 from 17 balls. Willey then carried that momentum in to the first over of the Afghan innings, trapping the batting side's danger man Mohammad Shahzad lbw for 4 after just 3 balls.
From that point on the upset, which had appeared almost certain at one point, became a remote possibility. England took wickets at regular intervals and an impressive rearguard action of 35 not out from 20 balls from wicketkeeper Shafiqullah Shafiq wasn't enough to stop England winning by 15 runs.
Afghanistan have impressed in the tournament so far, winning their pre-tournament qualifying section and troubling both Pakistan and Sri Lanka before their performance against England. Morgan was impressed.
"They play a great brand of cricket," Morgan said. If you underperform, you can come unstuck. We didn't adapt to the pitch - we didn't get that right. To get up to 143 Ali and Willey played really well. And I though we fielded well and bowled well."
Both sides play their final group games at the weekend. England play Sri Lanka in Delhi on Saturday before Afghanistan face the West Indies on Sunday.