England dismissed Pakistan for 304 on day one of the third and final Test in Karachi on Saturday.
In reply, England lost Zak Crawley in the very first over of the innings for a duck with Abrar Ahmed striking for Pakistan. At stumps, the visitors were 7-1 and trailed by 297 runs.
Earlier, England kept picking up wickets at regular intervals to keep Pakistan on the backfoot throughout the day.
Spinner Jack Leach bagged four wickets and debutant Rehan Ahmed claimed two wickets.
Pakistan, who have already lost the series with defeats in Rawalpindi and Multan, won the toss and opted to bat first on another flat track. But the hosts were rocked by England, who made early inroads in the first session in their bid for a clean sweep.
Spinner Jack Leach (4-140) first removed Abdullah Shafique with the new ball and took the catch that sent back Shan Masood off the bowling of paceman Mark Wood to leave Pakistan at 46-2 inside 13 overs, before Azhar Ali steadied the ship.
England went on the attack and 18-year-old debutant all-rounder Rehan Ahmed — who became their youngest men’s Test cricketer — had Saud Shakeel caught for 23 for his maiden wicket.
“The day before, Ben Stokes called me to his room with Baz (coach Brendon McCullum) and told me I was making my debut. I couldn’t sleep, couldn’t eat. I didn’t expect to play,” Rehan who finished with figures of 2-89, told Sky Sports.
“I think I rushed a little bit at first. It came out better than expected though. I know I got (hit for) a few boundaries. Stokes said to me ‘I don’t care about runs, I care about wickets’ and in the second spell I got some wickets.”
Babar, who hit nine fours in his 123-ball knock, soldiered on after part-timer Joe Root removed Mohammad Rizwan.
The skipper passed his half-century but was run out while attempting a single to leave Pakistan in further trouble.
Faheem Ashraf and Nauman Ali then fell to Rehan and Leach, but Salman held the fort and was rewarded with his second half-century of the series before also falling to Leach, who cleaned up the tail late in the day.