Rory McIlroy has arrived in court for the start of his multi-million dollar case against his former management company.

The top-ranked golfer is suing Dublin-based Horizon Sports Management and its leading agent, claiming he was misled into signing a contract with the company.

Wearing a dark suit and glasses, McIlroy arrived at the Dublin High Court on Tuesday morning for the start of proceedings. The case was quickly adjourned until the afternoon.

McIlroy has said in court papers that he signed the contract at Horizon's Christmas party "in circumstances of great informality," and without having seen a draft of the agreement before it was given to him to sign.

Horizon is counter-suing, claiming McIlroy owes it millions of dollars in commissions.

McIlroy left Horizon to form his own management company in 2013.