Essex must cope without star batsman Ravi Bopara as they look to rediscover their one-day form against Lancashire.
The all-rounder is in the England Lions squad competing in a triangular series against New Zealand A and Sri Lanka A.
The Eagles have suffered consecutive home defeats in one-day cricket, against Leicestershire and Birmingham.
Head coach Paul Grayson said; "We can't feel sorry for ourselves, we need to work hard and put a decent run of form together so we can progress."
Essex will not be using the slow, low pitch used in the One-Day Cup loss to Leicestershire last week.
Leicestershire scored 142 and won by 34 runs at Chelmsford on Thursday, with neither side completing their 50 overs on a slow pitch that often kept the ball low.
It was the same surface on which Essex scored their lowest first-class total of just 20 in a humbling defeat by Lancashire last year.