The 30-year-old ends his five-year spell at the helm, with his bow coming against Leicestershire in the LV=Insurance County Championship
Worcestershire are looking for a new club captain after Joe Leach revealed his decision to step away from the role at the end of the 2021 season.
The 30-year-old has led the New Road club across the formats since the end of the 2016 campaign, sharing the leadership of the T20 side with Moeen Ali and Ben Cox.
But after reaching the decision to stand down earlier in the campaign, Leach will lead Worcestershire for the final time against Leicestershire in the LV=Insurance County Championship.
Daryl Mitchell will also retire from cricket aged 37 after the game.
"It was a difficult decision to make, but one that I feel is right, not only for myself but also for the group as well," said bowling allrounder Leach.
"I’ve done it for five years, and I’m immensely proud of what I’ve managed to achieve in some difficult times for the club over that five years.
"I’ve had a lot of things to deal with on and off the field, and now I guess the time is right to focus on my cricket and getting back to really enjoying it and doing the best I can with the bat and the ball."
Coach Alex Gidman added: "His efforts as a captain have been of the highest order, and he has led the team through some very challenging times and has done an exceptional job.
"He should be very proud of his efforts, and I’m sure he will look forward to some more successful years as a bowling all-rounder for us.
"I know he will put a lot of effort into, firstly, his cricket, which is really important and, secondly, he will get right behind whoever the next captain is and still do a very job as a senior player.
"There is no doubt he has still got a huge amount to offer us. He is still a very big part of the plans and a great man for us to have around still."
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