CONCORD, N.C. (AP) -- Defending series champion Brad Keselowski believes he's still the fastest in Sprint Cup, even if his results four months into the season don't bear that out.

Keselowski is winless and stands seventh in points heading into the Coca-Cola 600 at Charlotte Motor Speedway on Sunday night. He opened the season with four straight top-four finishes and seven top 10s in the first eight races.

Recently, he's struggled to stay near the top with a 33rd at Richmond, an 11th at Talladega and a 32nd at Darlington.

The Penske driver says the speed is there. But unlike last year, the execution and luck needed to win isn't in abundance.

Keselowski hopes NASCAR's longest race is the place where things come together for him.