The Leon-based event will be the first rally the factory Citroen team has contested without Sebastien Loeb since Rally New Zealand in 2002.
While Hirvonen admits the team will miss Loeb, he is certain he is ready to start scoring big points for his employer.
"For me, this is where the season starts for real," said Hirvonen, who was fourth in Monte Carlo and crashed on the first morning in Sweden.
"We now have a very good idea of the level of our rivals. I think we can say that we'll have to fight on every stage [in Mexico] and produce a series of flawless performances in order to win rallies."
Mikko Hirvonen's AUTOSPORT diary column
Hirvonen has finished second to Loeb in Mexico for the last two seasons and without the defending champion in central America, increasing his confidence for this year's event.
"Last year, I was pretty close to Seb for long periods of the race," he said.
"I know I am capable of producing very good performances on this surface and I like racing here.
"We have done a lot of work in testing since Sweden, both on my driving and on the set-up of the car."