Cristiano Ronaldo has described the decision to uphold his five-match ban for pushing a referee in Real Madrid's Supercopa de Espana win against Barcelona as "incomprehensible".

After being booked for removing his shirt in celebration after scoring from the bench, Ronaldo was then shown a second yellow card after being adjudged by referee Ricardo de Burgos to have dived in the penalty area. 

Ronaldo then pushed the official in the back and was handed a five-match ban as a result, a decision that was upheld by Spain's Administrative Court of Sport on Tuesday.

But Ronaldo, who is already reportedly upset about an ongoing tax evastion case regarding his image rights, hit out at the news via social media.

"One more incomprehensible decision. From injustice to injustice, they will never overthrow me," Ronaldo wrote in Portuguese on Instagram.

"And as always I will come back stronger. Thank you to all who have supported me."

Madrid won the Supercopa 5-1 on aggregate against Barcelona and opened their league season with a 3-0 win at Deportivo La Coruna in Ronaldo's absence on Saturday.

He will be unavailable for Madrid's upcoming LaLiga matches against Valencia, Levante and Real Sociedad as their title defence continues.