Andrew Flintoff starred with the bat hitting a stunning 93 as Lancashire beat Derbyshire by 56 runs to book a spot in the Twenty20 Cup quarter finals.
Flintoff hit 93 from 41 balls, sharing a fourth-wicket stand of 99 with VVS Laxman (63) as Lancashire amassed 220-5, their best ever Twenty20 score.
The hosts reached 86-1 after a second-wicket stand of 69 between Greg Smith (56) and Chris Rogers (52).
But when both fell, Derbyshire stalled to close on 164-7, sending Lancashire through to the quarter-finals.
After winning the toss, Lancashire were given a solid platform by an opening stand of 35 between Laxman and Paul Horton (24).
Horton was caught by Rogers off paceman Nantie Hayward, and when Steven Croft and Faf du Plessis fell within eight runs of each other, Flintoff came to the crease with the score at 70-3.
His partnership with Laxman came in just 10 overs as he plundered six sixes and nine fours to record his highest ever score in the shortest form of the game.
The 31-year-old was denied a century by a brilliant one-handed catch from Smith on the deep midwicket boundary off the bowling of Ian Hunter, but his best performance with the bat since returning from knee surgery provides England with a timely pre-Ashes boost.
Flintoff (2-32) then bowled Derbyshire opener Graham Wagg for just four before Rogers and Smith combined to give the hosts hope.
When Rogers holed out to Mark Chilton off Croft's bowling, it was left to Smith try and see Derbyshire to an unlikely win.
He found a willing ally in Wavell Hinds (22), but when both were run out, defeat became inevitable and Derbyshire are now unable to qualify for the quarter-finals.
Lancashire will finish top of the North Division and are guaranteed a home tie in the last eight.