BOGOTA, Colombia (AP) — Serena Williams will face sister Venus in an exhibition in Colombia today, her first match since losing the US Open final two months ago.

Serena leads Venus, 13-10, in competitive head-to-head matches, and both sisters pledged to play hard during the match at Medellin, which is located at 1,500 metres (5,000 feet) in the thin air of the Andes.

Venus hasn’t played since pulling out of the US Open in September because of an immune system disease. Serena’s last match was her loss to Samantha Stosur in the title match.

“We are gong to be playing hard and give you guys a great show,” Serena said yesterday.

Venus acknowledged she will be the underdog against her younger sister.

“My opponent tomorrow night is definitely one of my biggest challenges.” Venus said. “I hope maybe she doesn’t play as well as normal so I can have a win… I’d like to be a winner too, so hopefully I can turn that around.”

Serena is currently No 12 in the WTA rankings and will be looking to try and return to the summit next season, a goal not even she is sure is possible.

“I don’t know,” Serena said. “I definitely see myself as at least in the top five. Obviously with me being someone who wants to be the best and the greatest, that’s not good enough for me. … We’ll see how it goes. It’s not like I’m starting at 100 so I have a good chance of getting there very soon.

“I didn’t start (playing) until summer,” she added. “I worked really hard to get some good results so that I would have a good year going and a good next year. So I think next year could be a good year for me to try to make some goals and see where I can end up.”