Lancashire 176 for 3 (Livingstone 43, Petersen 42, Brown 41) beat Durham 172 for 5 (MacLeod 45, Mahmood 3-31) by seven wickets
Lancashire's two England Lions men took the honours as the NatWest T20 Blast holders finally showed some of last season's prowess in a four-run win against Durham at Chester-le-Street.
They were revived by an unbroken stand of 48 in 3.5 overs between Paul Coughlin and Keaton Jennings, but when Coughlin needed to hit the last ball from Nathan Buck for six it landed ten yards short at long-on.
Durham finished on 172 for 5, virtually ending their hopes of qualifying for the quarter-finals, a target already looking beyond Lancashire when they arrived in bottom place in the North Group.
After being put in, Lancashire worked the ball into spaces as they ticked along to 88 for 1 after 12 overs before doubling the score in the remaining eight. The only six was a powerful straight drive by Livingstone, who used the ramp shot to hit four fours.
Chris Rushworth's first 11 balls cost one one run, plus four byes, which proved costly in the end. Alviro Petersen guided his first two fours deftly to third man before left-hander Luis Reece was struck on the helmet, prompting a delay while a new one was sent for. But in the next over Reece drove at Coughlin and edged behind. With only two runs coming off that over, Lancashire were 36 at the end of the Powerplay.
Karl Brown opened up on the return of Usman Arshad for the 13th over, taking 15 off the first four balls before Petersen drove well wide of off stump and edged behind for 42.
Brown departed in the next over for 41, lbw trying to sweep Scott Borthwick, but Livingstone and Croft upped the momentum.
Durham's top T20 scorer, Phil Mustard, made only 8 before skying Jordan Clark to wicketkeeper Tom Moores.
Mark Stoneman smashed Clark for two big sixes wide of long-on in the sixth over but when Croft, the third of Lancashire's three spinners, brought himself on for the tenth over Stoneman was bowled for 36 when trying to hit a straight ball over midwicket.
Calum MacLeod offered Durham's best chance of victory as he made 45 off 31 balls. But when stepped back to hit Mahmood through the off side he was yorked and the same fate befell Ryan Pringle and Gordon Muchall.
Coughlin hit Mahmood for a big six as the 19th over brought 16 runs, but the youngster still finished with 3 for 31 and Durham had left themselves too much to do.