Paddy Power's operating profit fell by 14% to €60.1m in the first half of the year after it was hit by a run of unfavourable sports results.
Paddy Power has more than doubled its annual profits since 2009 on expansion overseas and a strong performance online, where it leads the industry in betting via smartphones and tablets.
The Irish firm, which saw revenue rise by 7% in the period and increased its interim by 11%, said the second half of the year had started well after a successful FIFA World Cup, with a rebound in sports results.
It expects mid-teen percentage growth in earnings per share for the full year, despite an €11m headwind from product fees, new taxes and currency translation.
The betting firm said it had gained 795,000 new customers in the six month period - 148,000 of those during the FIFA World Cup.
Online active customer numbers are up 25%, according to the company, and Australia now accounts for almost 40% of the firm's profit.