Former world championships bronze medalist Sharon Cherop will be chasing after a personal best at the Buenos Aires marathon set for this Sunday in Argentina.

Cherop, who has a PB of 2:22:28, said she has been hard at work in preparing for the South American race. She wants to atone for her defeat by former world champion Ruth Chenpngetich in the 21km race during the Standard Chartered Marathon last month.

“I really don’t have a specific time that I will be chasing but I want some good time at the end of the day. I want to run better than I did in the half marathon,” said Cherop.

The 2012 Boston Marathon champion said she is buoyed by her performance at April's Milan Marathon, where she clocked 2:26:13.

In Milan, she edged out Ethiopian Ethlemahu Sintayehu (2:26:30) and compatriot Emily Chebet (2:28:08).

"I am really trying to come back stronger after being out for so long. I want to have a good time. I pray that it will be favourable this time around,” she said.

The 2002 world junior 5,000m bronze medalist has a good history in marathon running since winning bronze at the 2011 World Championships behind winner Edna Kiplagat and Prisach Jeptoo in an all-Kenyan podium sweep.

The Tirap Primary School alumna also won the Toronto Waterfront Marathon and finished third at the 2011 Boston Marathon before winning the race the following year.

“Weather can also be a factor and as athletes, we always look forward to favourable conditions,” said the former New Delhi Half Marathon silver medalist.

Apart from road running, she also competed at the Discovery Kenya cross country in 2002, where she was third. She has also won the Eldoret City Marathon.

Former world 10,000m silver medalist Paul Tanui will lead the men's contingent that has Cornelius Kibet, and Edwin Kibet among others.