Double defeat for Middlesex
Middlesex lost to Essex and Sussex in their NatWest T20 Blast double header at Lord's on Saturday.
Essex Eagles chased down a target of 181 for an eight-wicket victory and Sussex Sharks prevailed by 13 runs in a contrasting affair later in the afternoon.
Middlesex's day actually started well as Dawid Malan (86) and Eoin Morgan (77) put on a second-wicket stand of 118 to set up a total of 180-5 after they had been sent in by Essex skipper Pettini.
It would have been an even bigger score but for left-arm seamer Reece Topley (3-26) hitting back with three late wickets.
Pettini, leading the Eagles until Ryan ten Doeschate's IPL stint concludes, launched his side's run chase with an 81-run stand at 10-on-over alongside opening partner Alastair Cook.
Cook (22) and Essex debutant Jesse Ryder (15) both fell to left-arm spinner Ravi Patel (2-26) but Pettini and Ravi Bopara (45no) combined in a 69-run stand to complete the win with seven balls to spare.
Pettini finished 95 not out from 54 deliveries, including 14 fours and a six.
Middlesex faced a quick turnaround of just over an hour before they took on Sussex Sharks and again started the game strongly, a much improved display from their seamers limiting Sussex to 128 all out in 19.4 overs.
Toby Roland-Jones took the final two wickets with successive balls to earn figures of 3-26, while James Harris (2-10) and Dan Christian (2-23) each picked up two wickets.
But Middlesex's batsmen - so impressive earlier - floundered on the way to finishing short at 115-6, unable to come to terms with a disciplined bowling display from Sussex.
Medium pacer Steffan Piolet claimed the key wicket of Middlesex captain Morgan (30) via a top edge in the 16th over among his 2-15 haul.
Paul Horton and Tom Smith's 128-run stand allowed Lancashire to edge to a 12-run Twenty20 Blast victory over Worcestershire at Old Trafford.
When Lancashire posted 194 for three, Horton and Smith could have been forgiven for expecting a solid victory.
The visitors had other ideas, maintaining a brisk pace throughout and falling just 13 runs short of an impressive turnaround result.
Worcestershire reached 182 for five in their 20 overs - with little more than half a run an over between the two sides.
Lancashire claimed their first win of the tournament after losing out by 33 runs to Nottinghamshire on Friday night.