Shan Masood went on from his overnight 46* to score 156 and lead Pakistan to 326 all out before Pakistan's bowlers made early inroads into the England batting order.
England began the day brightly, with James Anderson removing Babar Azam before he had added to his overnight 69. Stuart Broad claimed his first wicket of the innings soon after, Asad Shafiq edging to slip for 7.
Mohammad Rizwan hung around alongside Masood through a testing spell of bowling until Chris Woakes drew a feather behind to end the wicket-keeper's resistance for 9 from 40 balls.
Shadab Khan played with intent as he and Masood began to get the scoreboard ticking over again, with runs starting to flow freely in a five-over period between lunch and the second new ball being taken. The pair dealt well with the new ball and Masood moved to his third consecutive Test century, becoming just the sixth Pakistan batsman to achieve the feat.
Shadab looked well set for a fourth Test fifty, but mis-executed aerial drive down the ground against Dom Bess's off-spin cost him his wicket as he skied one to mid-on for 45. Yasir Shah and Mohammad Abbas fell to consecutive deliveries from Jofra Archer, but Shaheen Afridi hung around for long enough to allow Masood to reach 150.
Broad finally dismissed the opener for 156, nipping one back on to Masood's pads. It was the first century by a Pakistan opener in England since Saeed Anwar in 1996. The England seamer took the wicket of Naseem Shah to wrap up the innings for 326, leaving England with just under a session to bat.
Opening bowlers Shaheen and Abbas got the visitors off to a flying start in the field, as the former dismissed Rory Burns in the opening over before the latter claimed both Dom Sibley and Ben Stokes in back-to-back overs.
Root and Ollie Pope managed to battle through the remainder of the openers' spells, with the latter adding runs at a decent pace to relieve some pressure. But the introduction of Yasir's leg-spin accounted for the England captain as he feathered a catch behind looking to cut a ball that was slightly too close to him.
Jos Buttler joined Pope, and the pair saw England safely through to stumps to finish on 92/4 trailing by 234 runs. Pope closed the day just four runs short of his fifth Test fifty.
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