England captain Alastair Cook will return to help Essex in their bid for promotion after being made available for the next two Division Two matches.
The 31-year-old scored 573 runs, including three centuries, in five games earlier in the summer.
Cook's first match back for the competition leaders starts on Tuesday against nearest rivals Leicestershire.
"Hopefully he can help us achieve our aims," head coach Chris Silverwood told the Essex website.
"It is always a bonus to have a man of Cook's calibre coming back to play for the club."
With four matches remaining, Essex are top of Division Two on 171 points from 12 matches - 23 clear of Leicestershire.
The second and final match that he is available for will be at home against Worcestershire, starting on 31 August.
Since his last appearance for Essex, against Kent in July, Cook skippered England in the drawn Test series against Pakistan.