The Real Madrid man suffered a painful blow during Thursday's controversial 3-1 defeat to Brazil in the opening game of the FIFA World Cup.
Croatia felt aggrieved by some of Yuichi Nishimura's refereeing, particularly his decision to award a penalty to Brazil after a coming together between Dejan Lovren and Fred with the score at 1-1.
However, the more pressing concern for coach Niko Kovac was the fitness of Modric, who went to hospital for a scan on Friday.
However, a statement published on the Croatian football association's website confirmed that an MRI "proved there is no fracture or ligament damage".
Modric is therefore expected to recover quickly, and should be available for full training on Sunday before Croatia face Cameroon in their crucial second Group A fixture three days later.