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Are there any other interesting aspects about this article?
In 2008, Cilic reached the semifinals at the Chennai Open.
How did he do?
Cilic made it to the fourth round of the 2008 Australian Open.
Did he win?
beating Jarkko Nieminen in five sets in the second round and knocking-out fourteenth seed Paul-Henri Mathieu.
When did he win the singles title?
At the 2008 Olympics, he reached the second round of the men's singles, beating Juan Monaco.
Was this the only Olympics he took part in?
CANNOTANSWER.

Question: Who did he compete against in the Olympics other than Juan?
Self-contained rewrite: Who did Marin Čilić compete against in the Olympics other than Juan?