Serena Williams from the US returns a ball to Danish tennis player Caroline Wozniacki during their Champions Battle exhibition game in benefit of the development of Danish sports on November 26, 2015 in Herning, Denmark. Wozniacki won the match 6-3 6-4. AFP PHOTO / SCANPIX DENMARK / CLAUS FISKER +++ DENMARK OUT +++ / AFP / SCANPIX DENMARK / CLAUS FISKER (Photo credit should read CLAUS FISKER/AFP/Getty Images)

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.

“It is (a goal), obviously,” Williams said.

“I’ve never done it, so we’ll see. I’m not putting any pressure on it.

“I took a lot of time off ... I ate a lot.

“I’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.”

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