Rory McIlroy believes that 2011 will turn out to be the defining year of his career.

The 22-year-old was in line to win the Masters in April before a meltdown caused him to miss out on the title, but victory at Congressional in the US Open a few months later saw him win his first ever major.

"I just think from the incredible low of Augusta to the incredible high of Congressional and everything that's happened since, that it's probably going to be the defining year of my career," McIlroy said.

"I think it has to change you. You do have to get harder as a person and I've noticed that a little bit about myself already. The Open was an eye-opener for me because I'd never really received that amount of attention before.

"You obviously want to try to be as open and honest as you possibly can but with so much attention on you it's hard. You have to put a little bit of a shield up."

The Northern Irishman recently signed a sponsorship deal with European bank Santander.