ESSEX were beaten in a last ball thriller on Sunday as Worcestershire strengthened their grip on the Pro-40 title.
Varun Chopra (62) and James Foster (52no) helped Essex reach 247 for five at Colchester but it proved not to be enough.
Worcester openers Vikram Solanki (62) and Steven Davies (61) set up a sound base for Daryl Mitchell (50no) to put Worcester in contention before Mitchell and Ian Fisher conjured up the victory with an unbroken partnership of 47 in the final five overs.
The scores were tied with one ball left, but Fisher's single to square leg from Chris Wright's final delivery saw the visitors to the winning post.
Essex will look to continue their LV County Championship Division Two promotion push on Wednesday at Chelmsford against struggling Leicestershire.
Last week Essex beat Surrey by nine wickets to record their fourth win of the season in the championship.
Danish Kaneria took six for 50 and Tim Phillips three for 61 as the visitors were dismissed for 190 to leave their opponents just 74 runs for victory with a session remaining.
Surrey had posted 428 in the first innings but Essex cam up with an impressive response, grabbing a first innings lead with 545 for nine which included a double hundred for England reject Ravi Bopara.
The 24-year-old saw his place taken by Jonathan Trott, who marked his Test debut with a century as England clinched the Ashes but Bopara is looking to make a return to the international arena.
He said: "I usually take things on the chin and get on with it.
"I am not a guy to make a fuss. I will come back a better player."