Serena Williams says winning a historic calendar grand slam is still her goal, despite struggling with injuries and turning 34 in 2015.

Speaking at a Manhattan event to honour her Sports Illustrated Sportsperson of the Year win, Williams admitted injuries took their toll this year, but said the grand slam was still a priority.

โ€œIt is (a goal), obviously,โ€ Williams said.

โ€œI've never done it, so we'll see. I'm not putting any pressure on it.

โ€œI took a lot of time off ... I ate a lot.

โ€œI'm working off a lot of that food now. I'm 34, so my (injuries) aren't perfect. I'm good though. Every day I'm sore in a new place, which is never fun.โ€

Williams is currently ranked No.1 in the world and won five titles in 2015.