The Colombian was handed a surprise start by Arsene Wenger in the Champions League game against PSG on Tuesday night, and he repaid the faith of his manager by putting in a sparkling performance in the 1-1 draw.
"We as a team take every opportunity, we work hard for that," said Ospina, who deputised for Petr Cech.
"This was a good match to show what I can do.
"For me, I need to work hard and be ready for every chance when I get to play.
"For us it was the biggest match of the group to play against Paris Saint-Germain, although of course we respect all the other teams in the group.
"It is a good draw and we can build on that but there's a long way to go."