Holders Hampshire will face Somerset in the Royal London One Day Cup final after Gareth Berg's five-wicket haul and half-centuries from Rilee Rossouw and James Vince helped secure a four-wicket win over Lancashire.

Rossouw, who scored 125 in last year’s final, reached his maiden ton of the campaign having abetted James Vince’s 79 in a century fourth-wicket stand.

Gareth Berg had laid the foundations of the victory with his maiden one day five wicket haul, and was brilliantly assisted by Mason Crane’s three for 42.

Berg claimed figures of five for 26 as he rammed through the tail, while legspinner Crane rattled through the middle-order as Lancashire were restricted to 241.

Meanwhile, Lancashire, who beat Middlesex in a thriller on Friday night, were condemned to their ninth straight List A semi-final defeat, as Hampshire look in search of being the first side since Sussex in 2008 and 2009 to win consecutive one-day competitions.

Saqib Mahmood struck with the fifth ball of Hampshire’s reply when he tucked Tom Alsop up to find an inside edge behind.

The fast bowler followed it up with two more scalps to take him to 50 List A wickets; Aneurin Donald slashed to point and then Sam Northeast chopped onto his own stumps.

That left Hampshire 23 for three and Mahmood celebrating figures of three for 20 from his first six over spell, following up the three for 15 in the same stint against Middlesex.

Vince ignored the wobble happening at the other end and played a pair of delightful square drives and a pull as he dug Hampshire out of trouble with a 55-ball half century.

The captain guided Rossouw through a sticky start to flourish into a 122-run partnership for the fourth wicket.

Rossouw made it to fifty off 69-balls, with back-to-back boundaries off James Anderson, the first a sumptuous straight drive and then a pumped pull.

The stand was ended by a sharp piece of fielding from Steven Croft, but Rossouw continued to slide through the gears, while Liam Dawson found important boundaries at the other end in a 59-run collaboration. Hampshire made it back to Lord’s when James Fuller scored the winning runs with six balls to spare.

Earlier, Lancashire won the toss and elected to bat first on the same wicket used by England and Pakistan a day earlier, a match which bore 734 runs for 10 wickets.

Keaton Jennings and Liam Livingstone put on 37 for the first wicket before the latter was bounced out by Fidel Edwards – with Crane taking a simple catch on the square-leg boundary.

Alsop once again proved his increasing stock behind the wicket when he produced a stunning full-length dive to catch Croft – Alsop is the wicketkeeper with the most dismissals in the competition, with 13 snaffles and five stumpings.

Jennings and Jake Lehmann rebuilt again with a 67-run stand, which saw the England opener move to his fifth One Day Cup 2018 half century in 56 balls.

But Crane entered the attack for a quick bang-bang to have Jennings castled with a straight ball that cannoned into leg stump and Dane Villas caught slapping to Vince at extra cover.

Australian Lehmann notched his 50 in 53 deliveries but was another victim of failing to convert when he slog swept Dawson to Fuller on the deep midwicket boundary.

From that point Hampshire took control, stifling Rob Jones to 38 from 62 balls before Crane picked up the last of his trio of scalps when slogged to long-on.

Berg cleared up the tail, seeing off Josh Bohannon and Graham Onions within four balls before bowling Anderson and having Mahmood caught by Vince – to bowl Lancashire out.