|England 200 (19.5 overs): Buttler 59 (39); Hasnain 3-51|
|Pakistan 155-9 (20 overs): Mahmood 3-33, Rashid 2-30|
|England won by 45 runs|
England's spinners squeezed Pakistan to claim an emphatic 45-run victory in the second Twenty20 and level the series at 1-1.
Although Jos Buttler, Moeen Ali and Liam Livingstone - who twice hit sixes out of Headingley - all sparkled with the bat, England failed to post a total that would have put Pakistan out of the game.
From 137-3 in the 14th over and 164-5 in the 16th, England lost their last five wickets for 36 runs to be bowled out for 200.
However, England's trio of spinners, led by Adil Rashid, superbly exploited a pitch that rapidly deteriorated.
Rashid claimed 2-30, fellow leg-spinner Matt Parkinson 1-25 and off-spinner Moeen 2-32 as Pakistan lurched to 155-9.
The series decider is at Old Trafford on Tuesday at 18:30 BST.
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Experimental England level series
After the thrilling entertainment of Pakistan's 31-run win in the series opener, this was another thoroughly enjoyable contest, played in front of a full house on a baking hot day.
England stuck with their plan of experimenting with October's World Cup in mind. Captain Eoin Morgan was rested, Jonny Bairstow shifted down the order to number six and Moeen's off-spin employed after he did not bowl on Friday.
With the World Cup set to be played in the United Arab Emirates and Oman, most encouraging will be the combined performance of leg-spinners Rashid and Parkinson, who lined up in the same England team for the first time.
The hosts' total looked no more than par, only for Rashid and Parkinson to stifle Pakistan on a pitch that became increasingly responsive to the slow bowlers.
Livingstone shines again
Fresh from his dazzling 42-ball century on Friday, Lancashire's Livingstone was again striking the ball with awesome power.
Buttler, captaining in his first match for a month because of a calf injury, added the early impetus with his 59 from 39 balls, putting on 67 with Moeen, who crashed 36 from 16.
But it was Livingstone, himself sharing 52 with Buttler, who provided the stand-out moments.
A first straight six out of the ground, off spinner Imad Wasim, was handsome, but a second, off the pace of Haris Rauf that went over the new stand and onto the rugby ground, was a massive hit.
Livingstone was run out for 38 from 23 balls when he failed to respond to Tom Curran's call, a signal for England to lose momentum against a Pakistan side that held their length with the ball and caught well in the field.
Still, England have not lost a T20 when they have posted 200 batting first, a record that never looked in danger.
England spinners stifle Pakistan
In hindsight, the way the pitch behaved suggested Pakistan made a mistake in fielding first after winning the toss, but that should take nothing away from the way England bowled.
Although captain Babar Azam and Mohammad Rizwan reprised their stellar opening partnership from Friday by adding 50 in the powerplay, after Saqib Mahmood had Babar miscue to extra cover the spinners took over.
Rashid bowls with a fizzing pace and possesses a dangerous googly. Parkinson is much slower, using his flight and guile. At one stage they bowled five overs in tandem that cost only 28 runs and brought two wickets - both to Rashid, one a superb caught and bowled to remove Rizwan. The life had been sucked from the chase.
Moeen followed up with two wickets in an over, while Parkinson finally got his reward from the last ball of his spell when Azam Khan was stumped.
In all, England sent down 11 overs of spin, the most they have bowled in a T20, before seamer Mahmood nipped in at the death for 3-33.
'A ruthless performance' - what they said
England captain Jos Buttler on BBC One: "I was a bit nervous coming into today but I enjoyed it. It was great to be back out there.
"We've got a lot of options and that's fantastic for us. It was nice to give Moeen that opportunity today. It was a great all-round performance from him and the leg-spinners bowled really well together."
Former England captain Michael Vaughan: "England were very, very impressive, particularly with the ball in hand. All the bowlers had a good afternoon out. And you expect that from England with the bat."
Former England batter Ebony Rainford-Brent: "It was a ruthless performance and England made it look easy in the end."
Pakistan captain Babar Azam: "We started well but they got 20 or 30 runs extra. After six overs of our chase we couldn't continue the partnerships."
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