England beat Pakistan by 330 runs on Monday, winning with more than a day to spare as they levelled the four-Test series at 1-1 following the tourists’ 75-run success at Lord’s.
Cook and Root scored 506 runs between them for just twice out at Old Trafford.
After England captain Cook won the toss, they did the bulk of the damage in a huge first-innings total of 589 for eight declared.
Man-of-the-match Root made a Test-best 254, while left-handed opener Cook’s 105 extended his England Test century record to 29.
With vice-captain Root promoted up the order to number three this series, the pair shared a second-wicket partnership of 185.
Then, after Cook decided against enforcing the follow-on, they piled on the runs again in England’s second innings.
Cook made an unbeaten 76, which included a 55-ball fifty — the fastest of his Test career — while Root was 71 not out in a total of 173 for one declared.
“(Joe) is a world-class player, and it was a great innings — one of the best I’ve seen — to really set up the game for us,” said Cook.
“One thing he does very well is keep the scoreboard ticking over, so blockers like me get carried away,” added a self-deprecating Cook.
Cook and Root’s run spree on Monday — they added 75 runs in just nine overs before the declaration — left Pakistan needing a massive 565 for victory.
James Anderson, returning to England duty on his Lancashire home ground after missing the first Test with a shoulder injury, scuppered any slim hopes of a shock win for the tourists by promptly reducing Pakistan to 25 for two.
Pakistan were eventually dismissed for 234, an improvement on their meagre first-innings 198.
The only downside for England on Monday was when all-rounder Ben Stokes went off midway through his sixth over with a right calf injury that will be scanned on Tuesday.
But Cook said Stokes, returning to England action for the first time since injuring his left knee in the Sri Lanka series opener in May, was a “fairly big doubt” for next week’s third Test at Edgbaston.
In the meantime Cook was delighted by the way England had upped their game after being well below their best at Lord’s.
“It was us showing the standard of cricket we can play,” he said.
“We didn’t do that at Lord’s. We didn’t bowl as well as we could (there), certainly didn’t bat as well as we could, and dropped too many catches.
“We put most of those things right in this game.”
For Pakistan captain Misbah-ul-Haq, this was a chastening defeat.
“Our batting was a big disappointment,” said Misbah. “To get 198 and 234 on a good pitch — you can’t take that.”
Pakistan leg-spinner Yasir Shah took 10 for 141 at Lord’s but only managed figures of one for 266 at Old Trafford.
Misbah, at a loss to explain the discrepancy, said: “It was maybe tiredness, a lot of overs — I don’t know.
“It was a big difference. But he is a strong character, and before the next Test he will analyse what went wrong — and come back.”
Another concern for Pakistan was the form of openers Mohammad Hafeez and Shan Masood.
Not since 1996 have a Pakistan opening pair recorded a fifty stand in a Test against England in England, with Hafeez and Masood’s best so far this series the 38 they managed in the first innings at Lord’s.
Pakistan have three ‘reserve batsmen’ in their squad in Iftikhar Ahmed, Mohammad Rizwan and Sami Aslam.
They will hope to press their case for a Test call-up in a two-day tour game against Worcestershire starting on Friday.
“It’s a chance for us and them at Worcester,” said Misbah.
“Some of them (the current top order) are getting starts but not converting those starts into bigger innings.
“We need to make it big and that’s what we’re missing,” he added.