Lancashire 265 for 5 (Prince 76, Katich 57*) beat Surrey 264 for 8 (Davies 53, Roy 50) by five wickets
Simon Katich hit a match-winning 57 from 37 balls to lead Lancashire to a five-wicket win over Surrey at Guildford.
When Gareth Cross, who contributed an unbeaten 24 off 15 balls, joined his captain in the middle, the visitors needed a testing 76 in nine overs for their Group B victory. But Katich breezed to an unbeaten half-century to see the Red Rose to their victory target of 265 with 15 balls to spare.
Katich, the Australian left-hander, took the game by the scruff of the neck by pulling Jon Lewis off the front foot for six and clubbing five successive fours off Zander de Bruyn. Cross got in on the act by launching Jade Dernbach back over his head for a maximum to shave the requirement to 25 in five overs, with the Powerplay still to come.
Jason Roy, with 50 and Steven Davies, 53, had earlier laid the foundations for what should have been a mammoth Surrey total by putting on 101 for the first wicket. Davies hit three sixes en route to a 26-ball half-century, as Surrey raced to 100 without loss inside 12 overs. Davies would have had a fourth maximum had it not been for an excellent catch on the midwicket boundary by Stephen Moore.
Roy moved to a run-a-ball fifty before backing away and toe-ending an attempted cut off Jordan Clark through to the wicketkeeper.
Ricky Ponting had just five when he was caught at deep midwicket by Ashwell Prince, who then lost balance and stepped over the rope. But, in the 20th over, Ponting was beaten by Moore's direct hit from midwicket to leave Surrey 139 for 3.
Six overs later, Katich pulled off a superb one-handed catch at cover off Steven Croft to see the back of Vikram Solanki for 34.
Glen Chapple returned to the fray to trap Gary Wilson leg-before. Surrey continued to falter with Azhar Mahmood holing out to long-on and, three balls later, Zafar Ansari going caught behind off Kyle Hogg without scoring.
Lewis went to a skied pull before De Bruyn and Chris Tremlett gave the hosts a defendable total by adding an unbeaten 44 in less than five overs. The final over saw Hogg lifted for two straight sixes, the second of which took De Bruyn's contribution to 34 off 26 balls.
In reply, Lancashire were handed a decent start by Prince and Moore. Prince, who launched Ansari for a straight six, reached his fifty in 43 deliveries, but not before Lewis had struck with 85 on the board by having Moore caught off a leading edge for 30.
Prince and Croft combined for a further 55 in nine overs before Croft was caught behind off Dernbach for 25.
The turning point appeared to come when Azhar Mahmood had Prince caught at mid-off for 76 and Brown chopping on next ball. But Clark kept the visitors in the hunt by hitting 27 in as many deliveries before handing the baton to Katich.