England in sight of victory after Brook's triple hundred

England's bowlers sparked a Pakistan batting collapse after a brilliant triple century by Harry Brook and Joe Root's double hundred had them closing in on victory in the first Test in Multan on Thursday.

Brook smashed 317 and Root a record-setting 262 in England's mammoth 823-7 declared, giving the visitors a 267-run lead.

Pakistan in reply were struggling on 152-6 at the close of the fourth day, with Agha Salman unbeaten on 41 and Aamer Jamal on 27 not out.

The pair added a fighting 70 for the seventh wicket, with the home team still needing 115 runs to avoid an innings defeat.

Pakistan's collapse marked a quick turnaround to the match after a flat Multan stadium pitch saw 1,379 runs scored for the loss of just 17 wickets.

Brook and Root earlier put on 454 for the fourth wicket as England piled up the fourth-highest total in Test cricket history.

It was England's highest in Tests, eclipsing the 411-run fourth-wicket partnership by Peter May and Colin Cowdrey against the West Indies at Birmingham in 1957.

England declared their innings 33 minutes before tea and Chris Woakes dismissed Abdullah Shafique with the first ball of the innings.

It was a familiar story of second innings failure for Pakistan as skipper Shan Masood (11), Babar Azam (five) and Saim Ayub (25) were dismissed before the total passed 50.

Masood was dropped twice on five and seven but miscued a shot off pace bowler Gus Atkinson, who also had Azam caught behind with a sharp delivery.

It became 5-59 when Mohammad Rizwan fell for 10 to fast bowler Brydon Carse.

Saud Shakeel and Agha took Pakistan to 82 when spinner Jack Leach came into the act, getting Shakeel caught behind for 29.

Atkinson has figures of 2-28 and Carse 2-39.

Brook and Root enjoyed a run-feast with career-best knocks.

Brook completed his triple century with a boundary off part-timer Ayub, reaching the mark off 310 balls before he top-edged a sweep off the same bowler and was caught by Masood.

"It is amazing," said the 25-year-old Brook.

"I am lost for words, to be honest, I'm just happy that the team is in a strong position to win the game... It's been an incredible thing."

He cracked 29 fours and three sixes in his 439-minute stay at the crease.

Root -- who broke Alastair Cook's England Test run record of 12,472 on Wednesday -- fell short of a triple hundred when he was trapped leg-before by Agha after a marathon 10 hour-stay during which he hit 17 fours.

Ayub (2-101) and Naseem Shah (2-157) were the most successful Pakistan bowlers.

England resumed on 492-3 in the morning and looked for quick runs, which Root and Brook provided despite Pakistan's defensive leg-side bowling, adding 166 runs in 29 overs in the session.

Root's previous best of 254 was also against Pakistan at Manchester in 2016.

Brook's previous best was 186, scored against New Zealand at Wellington last year.

Pakistan's only chance came in the first hour when Root, on 186, failed to keep down a pull shot off Shah but Azam spilled the regulation chance at mid-wicket.

Root took full advantage and with a single off spinner Salman completed his sixth Test double-century, which came in 517 minutes off 305 balls.

Pakistan were without frontline spinner Abrar Ahmed, who suffered a fever and did not take the field on Thursday.