"If nothing extraordinary happens she will compete in Lappeenranta," Jukka Harkonen told Reuters on Thursday.
"She is suffering from mild 'flu, which is the only thing that could impact it, but we have booked flights and agreed on everything."
Semenya, who was cleared to compete as a woman by the International Association of Athletics Federations (IAAF) on Tuesday, has not run competitively since undergoing gender tests at the Berlin world championships in August.
The Lappeenranta Games will be held on July 15 in the southeastern Finnish town, some 220 kms from the capital Helsinki.
"There are a few small competitions held in July and there is no point to start from a big competition. It better to get competition feeling from smaller ones," Harkonen said, adding that the fact that he was Finnish also had some bearing on the decision.
He said there had been talks about other competitions which Semenya might attend after Lappeenranta, but that no decisions had been made.
Semenya sprang to prominence last year with her rapid improvement over 800 metres. Her winning time in Berlin of one minute 55.45 seconds was the fastest of 2009.
On Wednesday, the 19-year-old South African ran 600 metres in fitness tests to determine if she was ready to compete after the long absence.
Her coach Michael Seme has said Semenya will not compete in the world junior championships in Canada later this month but might run in the African championships, which start on July 28.
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