History maker Rehan Ahmed enjoyed an impressive start to his England career, helping Ben Stokes' side bowl Pakistan out for 304 after Babar Azam won the toss and vowed to try and "put runs on the board and put pressure on".
England are eyeing a historic 3-0 whitewash in their first series in Pakistan in 17 years and made two changes to the side which won in Multan, with wicketkeeper Ben Foakes returning and Ahmed becoming the youngest man to play Test cricket for England.
And Stokes decided to throw Ahmed into the action early, handing him the ball after just 17 overs had been bowled. While the youngster initially proved expensive, conceding 37 runs from his five-over spell before lunch, he quickly settled into his work after the break and claimed his maiden Test wicket when he outfoxed the in-form Saud Shakeel.
It was an incredibly impressive start to his international career and he ended the day with figures of 2-89 from 22 overs, having also pinned Faheem Ashraf lbw. And while Ahmed was perhaps the star of the day, it was a good team performance from England in the field as every bowler chipped in with crucial wickets.
Pakistan, however, will be incredibly disappointed with their innings as they failed to make the big score Babar was hoping for when he won the toss on a flat pitch. The likes of Shan Masood, Azhar Ali, Mohammad Rizwan and Babar himself were all at fault for their dismissals, with the skipper run out after a fatal hesitation.
Abdullah Shafique was the first wicket to fall, getting pinned lbw for eight by Jack Leach, who finished with 4-140. Masood was then bounced out by the express pace of Mark Wood after making a positive 30 off 37 balls, before Ollie Robinson got the retiring Azhar Ali caught down the leg side for 45 right at the end of the morning session.
After lunch Pakistan lost several more soft wickets, with Rizwan embarrassingly smacking a Joe Root full toss straight to Stokes at mid-on after Ahmed had brilliantly set up and dismissed Shakeel. Babar, meanwhile, was batting imperiously for Pakistan and looked dead set to make a ninth Test century.
However, he was brilliantly run out by Foakes after setting off late for a quick single as Pakistan once again contributed to their own downfall. Agha Salman did impress with a fighting fifty from number seven, but England will be very happy with their day's work after bowling the hosts out for 304 and...
Ahmed makes history
At 18 years and 126 days old, Ahmed broke a record hold by the legendary Brian Close as he became the youngest man to play Test cricket for England. The last time England handed a debut to a player who had only played three first-class games or less was Alfred Archer all the way back in 1899.
Ahmed's dad, Naeem, was invited into the team huddle as his son was presented with his cap by Nasser Hussain and could not contain his joy. And the teenager was impressive, settling into his work well after bowling an expensive first spell before lunch.
He claimed his maiden Test wicket by setting up Shakeel perfectly, with a googly spinning past his outside edge before finding the inside edge the very next ball with a traditional leg-spinner. The ball popped straight up into the air off Shakeel's pad and was brilliantly caught by a diving Ollie Pope in a perfect example of what wrist spin can offer, particularly in the subcontinent.
Ahmed looks a really impressive prospect for England and surely has a big future on the international stage. "He is 18 years of age and leg spin takes a long time to master," said Pakistan legend Waqar Younis on BBC Test Match Special. "The talent is there. England have to really look after him. He will be a force in the coming years."
Leach takes the new ball
Stokes has wholeheartedly backed Leach since taking over as captain and has handed him the new ball on four occasions in ten Tests so far, including in both innings in Multan. In Karachi, Leach opened the bowling once again alongside Robinson and took the early wicket of Shafique in just his third over.
It is the first time Leach has taken the new ball in the first innings of a Test, meaning he is the first England spinner to do so since fellow Somerset left-armer Jack White did it against Australia at Headingley in 1921.
It is yet another example of Stokes' willingness to experiment in the field and it has brought England great success so far, with even 177 Test veteran James Anderson saying his approach is "making me think differently about the game".
Babar's "reckless" run out
Pakistan suffered several reckless dismissals in their innings and, while Rizwan hitting a full toss straight to Stokes was the worst of the lost, Babar's run out was the most significant. The Pakistan skipper had been batting brilliantly, holding the innings together and looking set for a well-deserved hundred.
However, a crucial hesitation while looking for a quick single saw him brilliantly run out by the combination of Harry Brook and Foakes for 78. With Pakistan only just passing 300 on what was a pretty flat day one pitch, that run out may well prove crucial as the day goes on.
"Pakistan have lost another reckless wicket here," former England spinner Vic Marks said on BBC Test Match Special of Babar's dismissal. "It was always going to be tight, Brook did well and Foakes did even better.
"The real problem for England has gone. Agha Salman will be feeling dreadful. The pressure is on Pakistan."
Foakes a difference maker
While Pope certainly did an impressive job behind the stumps as a stand-in wicketkeeper in the first two Tests, Foakes showed exactly why his skipper believes he is "the best keeper in the world".
His imperious glove work played a key role on day one as England picked up the important wickets of Azhar and Babar. Foakes took a stunning diving catch down the leg side to dismiss Azhar, similar to the one Pope took to dismiss Shakeel in Multan except this one was definitely taken cleanly.
He also brilliantly ran out the in-form Babar when he looked set for another hundred. And although Pope deputised admirably, he did miss a few difficult chances, particularly in the first Test, with Foakes now showcasing how important a world-class wicketkeeper could be to this England side.
Abrar the magician
After picking up 11 wickets on a dream debut in Multan, Abrar once again impressed in a short two-over spell before the close of play as he pinned Crawley lbw for a duck. It may yet prove a key wicket as the game wears on and certainly gave Pakistan a boost heading into day two.
There was plenty of spin on day one on this Karachi track to give Abrar and fellow spinner Nauman Ali some confidence and it will be interesting to see how England play him tomorrow.
Former England spinner Alex Hartley was full of praise for the leg-spinner on BBC Test Match Special, saying: "Isn't Abrar good? What he's done there is bowl the ball seam up. He's gone back of a length and then fuller."
