Lancashire were in danger of squandering a winning position against Hampshire as Andy Flintoff and Mark Chilton tossed their wickets away at the crucial stage of the run chase.
But Neil Fairbrother and Ian Austin, veterans of almost 350 Sunday appearances between them, linked up to take Lancashire home with four wickets and three balls to spare.
And with another old stager, Yorkshireman David Leatherdale, snatching a tie for Worcestershire at Essex, Lancashire now have a two point cushion at the top of the table - with games against title rivals Warwickshire, Gloucestershire and Essex to come.
Fairbrother h it 88 from 104 balls, the best of his four Sunday half centuries this season, until he was bowled by Stuart Milburn in the 37th over.
And then Austin, who had already claimed 2-35 in a typically accurate bowling stints, took over, thumping three boundaries in five balls to end with 27 from 27, surprisingly his best Sunday score of the year.
Coach Dav Whatmore suggested that the youngsters could have been in trouble if Lancashire hadn't won, saying: ``I was a little bit angry with a couple of the wickets we lost.
``I would have been pleased to see a couple of the younger ones show a bit more responsibility, but it wasn't to be and we had to rely on Austin and especially Fairbrother.''
Lancashire had been cruising at 115-2 after restricting Hampshire to 210-9, with Graham Lloyd joining Fairbrother to put on 66 in 11 overs.
But after Lloyd went lbw to Hampshire skipper John Stephenson, Flintoff lofted former England off spinner Shaun Udal straight to deep mid-wicket and Chilton was stumped to put the pressure on Fairbrother.
Chilton had done well with the ball, dismissing Hampshire dangermen Robin Smith and Matthew Hayden to earn 2-15 in his first four overs before taking some stick in his fifth.
But two more established fixtures in Lancashire's one-day team, Gary Yates and Peter Martin, also played their part in a top class performance in the field. Yates earned 1-29 in his eight overs and took a sensational one-handed catch at long on to get rid of Hayden for 55, while Martin claimed three late victims to remain the leading Sunday wicket taker in the country with 22 in 11matches.
``It was a pretty good performance in the field - if we can do that in all our other matches, we're going to be in a handy position,'' added Whatmore.
But Lancashire are now out of action in all competitions until next Wednesday, when they face Warwickshire at Blackpool in the Championship.