Skrtel will be fit for Slovakia opener
The Liverpool player went off during a 3-0 friendly win against Costa Rica in Bratislava and was taken to hospital for a scan.
"Based on preliminary conclusions, there is no damage to the tissue (in his ankle)," SITA quoted Ladislav Pavlovic, the national squad's chief physician, as saying.
"The ankle swelling is still significant and the injury requires treatment for more than three days, as previously suggested," he said. "Martin is a fighter and he will be fit for the first match of the tournament against New Zealand."
Slovakia's squad leave for the finals in South Africa on Tuesday and face New Zealand in their first Group F match on June 15.
Napoli midfielder Marek Hamsik, Slovakia's most influential player, missed Monday's group training because of minor problems.