ESSEX James Foster hit the first five balls of an over from Durham's 19-year-old leg-spinner Scott Borthwick for six to propel Essex to a seven-wicket win in the Pro40 League match at Chester-le-Street today.

Borthwick had bowled well, tying up Alastair Cook despite his second successive one-day century - but when Essex needed 33 off four overs Foster began to pepper the leg-side boundary.

The first two sixes were swept, the second only just clearing Liam Plunkett, then a short ball was pulled over the same fielder.

Two more sixes were bludgeoned to the same area to set up the prospect of six sixes in an over winning the match. But Borthwick speared the last ball past leg-stump, and it went for four wides.

England one-day discards prospered on an excellent pitch as Phil Mustard's century for Durham was upstaged by Cook, Foster and Graham Napier.

With neither side seriously in the running for Pro40 League honours, Essex roared past Durham's 276 for six with three overs to spare.

Although Durham do not field Steve Harmison, Graham Onions and Callum Thorp in this competition, Cook left the Sky TV audience wondering how England could leave him out as he made an unbeaten 104 to follow his century against Hampshire last week.

The victory chance was set up by Napier's 63 off 49 balls; then Foster went in at 155 for three in the 25th over and made 83 not out.

It seemed Durham were testing the mettle of their youngsters, because they had Borthwick and Ben Harmison bowling at a crucial stage.

When the leg-spinner conceded only five singles off the 33rd over Essex needed 58 off seven, but 12 came off the next over from Harmison.

Cook reached his hundred off 102 balls but was unable to press on during another good over from Borthwick, which cost only four - leaving Foster to complete the task in sensational style.

Mustard's hundred was his second in one-day cricket, the first coming in the Friends Provident Trophy at Northampton two years ago.

It was the fourth time he had passed 50 in six Pro40 innings this season. But he initially played second fiddle to Ian Blackwell in an opening stand of 100 in 13 overs.

Blackwell hit two huge sixes in reaching 50 off 40 balls but led a charmed life. He edged Napier just over slip on five, then inside-edged the same bowler just past leg-stump for four - and on 42 survived a sitter to Tim Phillips at cover.

Durham had 79 on the board after 11 overs, when Danish Kaneria came on and conceded 15 runs in his first over. It included a glorious straight six, which easily cleared the sightscreen to take Blackwell to his half-century.

He fell for 59 when he miscued Napier to Cook at deep mid-off, but Mustard drove two sixes off Kaneria on the way to his 99-ball century before falling for 102 when he pulled the Pakistani to wide mid-on.