Mitchell, a product of the county's academy, scored 922 first-class runs in 2008 - his first full season of senior cricket - to play a leading role in helping the county gain promotion to Division One of the LV County Championship.

Mitchell's opening partner, Stephen Moore, put pen to paper on a new three-year contract last month despite attracting interest from 11 counties.

"I was disappointed not to get to 1,000 runs by the end of the season," said Mitchell. "But I averaged over 40 and we won promotion in the Championship and stayed in Division One of the Pro40 League and now I have got a new contract - so it's not been a bad year."

He is one of four players to commit their future with Worcestershire.

All-rounder Gareth Andrew, signed from Somerset last winter, has signed a new two-year deal until the end of the 2010 campaign.

Paceman Chris Whelan, recruited from Middlesex at the end of last season, and reserve wicketkeeper Josh Knappett have signed new 12-month contracts.