Francois du Plessis hit a majestic century, his second in three innings, to send Lancashire Lightning into the semi-finals of the Friends Provident Trophy at the expense of holders Essex Eagles.

The South African reached three figures off only 71 balls to become the fastest one-day centurion of the English summer so far. He broke his own 76-ball record set against Derbyshire earlier in the competition.

The 24-year-old, who is one of a whole host of Kolpak players concerned about their futures in county cricket beyond 2009, went from fifty to 100 in only 19 balls to fire his side to 262 for six off 50 overs.

In total he hit five fours and seven sixes to help accrue a mammoth 121 runs off the last 12 overs, including 63 runs off the five overs of batting powerplay. He finished unbeaten on 113 off 75 balls.

Left-arm spinner Gary Keedy then picked up four wickets for 45 runs as Essex were bowled out for 195 with six overs to spare. Lancashire, who won by 67 runs, will host Hampshire Hawks in the last four on July 5.

Essex opening bowler David Masters had put his side in healthy shape with a superb 10-over spell of two for 14 after the visitors won the toss and elected to bowl.

He claimed the wickets of Paul Horton and Steven Croft to leave Lancashire at 154 for five in the 41st over. Part-time left-arm spinner Grant Flower also took two wickets for nine runs in three overs.

When du Plessis came to the crease, Lancashire were 86 for three in the 27th over. Fellow South African Ashwell Prince had hit 40 and Mark Chilton 43 on a slow track.

Du Plessis reached his fifty in the 45th over off 52 balls before really setting about the Essex bowling. He looked particularly strong through and over cover.

Lancashire continued their momentum with ball in hand, reducing the Eagles to 23 for two in the 10th over of their chase.

England Test opener Alastair Cook (12) was the victim of a fine running catch by Sajid Mahmood at mid-on off the bowling of Glen Chapple.

And that man du Plessis was back in the action again, this time with a precision throw to get rid of in-form Varun Chopra for a duck.

Mark Pettini (24) and Matt Walker later departed to Kyle Hogg and Keedy to leave the score at 76 for four in the 24th.

Mahmood (two for 29 off eight), Lancashire's leading FPT wicket-taker, got in on the act in the 29th over by removing James Foster courtesy of a diving catch by Chapple as Essex slumped to 99 for five.

Flower was Essex's last hope but, when he went caught at mid-wicket by Horton off the bowling of Tom Smith for 44 off 57 balls, Lancashire were virtually home and hosed with the score 130 for six in the 36th.

Graham Napier followed to Mahmood for 19 before Kaneria, Chris Wright and Ryan ten Doeschate (41) all fell to Keedy.