The tourists put their Test series whitewash behind them to make a winning start in the four-match series, with Cook registering England’s first hundred of the tour.
After winning the toss, the skipper led the way with his century, ably supported by Essex team-mate Ravi Bopara, who survived an early lbw decision before making a composed 50.
Steven Finn once again impressed in an England shirt, producing a devastating opening spell to remove Pakistan’s top-four batsman and return figures of 4-34.
“It was a really good day,” said Cook, speaking after the game.
“It’s been a hard tour, it’s been frustrating. We haven’t played up to our potential, but today showed what good players we have. It’s always good to start well as a side and an individual.”
Despite Saeed Ajmal once again bamboozling the English batsman and returning figures of 5-43, Cook’s side posted an impressive 260-7 from their 50 overs.
The opener’s stand of 131 with Bopara calmed English nerves and brought some respectability back to the side after three heavy Test defeats.
Asked what had been the difference today in light of the poor Test performances, Cook replied: “I don’t know, it’s a different format. The pressure of men around the bat is gone.
“We got a really good score on the board. The way Ravi played, coming in after we lost two quick wickets, was a good knock. He took the pressure off me and I just batted as long as I could.
“Then Steven Finn and the bowlers made it really hard for Pakistan.”
Cook’s opposite number, Misbah-ul-Haq blamed his batsmen for failing to deal with Finn’s opening assault, before left-arm spinner Samit Patel claimed three wickets to wrap up the result.
Shahid Afridi, who earlier bowled Kevin Pietersen and Jonathan Trott with successive deliveries, top-scored with 28 and entertained the crowd with some trademark blows before he fell to Patel, caught at long-off by Graeme Swann.
But this was only a brief highlight of a poor batting display from Pakistan and Misbah will want his side to move on quickly.
“They [England] played wonderful cricket, he said. “Their captain led their team by example. His innings was the key for them.
“Our batting was a matter of concern for us – 260 wasn’t a big score here. Batting under lights is difficult here but I think we have to do a bit of disciplined batting against the new ball.
It was just a bad day, one bad performance. We’ll come back, do the basics right and let’s see. It’s really important for us to come back.”
The two sides meet again at the same venue on Wednesday, before the series moves to Dubai for the remaining two ODI matches.
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