[5] After a short trial period, South African club Bloemfontein Celtic gave Ransford Osei a six-month contract in January 2012.

[10] In January 2015, Osei signed for South African Premier Soccer League side Polokwane City on a three-year contract.

[18] Osei went on to score two more goals against Germany and Colombia, to take Ghana into the last sixteen of the FIFA U-17 World Cup, where they met and defeated favorites Brazil despite playing the entire second half with only ten men[19] On 1 September, Osei set up the first goal and scored the second as the Ghanaians beat Peru 2–0 to take them into the U-17 semi-final match against Spain.

[20] Osei finished the U-17 World Cup with the Adidas Silver Shoe as the competitions second highest goalscorer,[21] coming second by one goal to Macauley Chrisantus of Nigeria.

A Striker described by FIFA.com as "an opportunistic goal machine"[26] with superb pace and movement,[27] young free-scoring sensation Osei was recognized by World Soccer Magazine as one of the 50 Most Exciting Teenagers on the Planet in their November 2007 Issue.

I'd love to have Patrick Kluivert's heading ability, the speed and ball control of Samuel Eto'o and the finishing skills of Thierry Henry.

"Whenever I miss chances I can't sleep at night," Osei, the adidas Silver Shoe winner at the 2007 U-17 World Cup, tells FIFA.com. "