The Real Madrid ace will have some special marking on Saturday.
"We have to irritate Cristiano Ronaldo from the start, we have to hit him and knock him down a couple of times, but without seeing a yellow card," Kjaer is quoted as saying by Lusa.
Denmark are leading their group with 16 points from six matches, while Portugal stand third on nine points.
Luís Mira, Goal.com
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