CHARLOTTE, N.C. � Mark Martin will drive a full Sprint Cup schedule for Hendrick Motorsports in 2010.

The 50-year-old Martin signed a two-year contract with Hendrick last summer, but the second year originally was to be a partial schedule. It will be Martin's 22nd full season at NASCAR's top level.

He will keep his seat in the No. 5 Chevrolet. Martin drove that car to a win at Phoenix last month that made him the third oldest NASCAR winner in history.

Martin's decision likely will impact Brad Keselowski's future with the team. Keselowski, who has a developmental deal with Hendrick, wants to race a full Cup schedule in 2010, but Hendrick does not have an open seat available.

In his fifth career start, Keselowski got his first Cup win two weeks ago at Talladega.