Flutter Entertainment, which owns Paddy Power, said it expects its earnings for this year will reduce by around £90m - £110m (€100m-€122m) as sporting events are cancelled on the back of the coronavirus.
Last year Flutter reported underlying earnings of £385m (€426m).
The reduction in earnings estimates is based on a scenario where restrictions on sporting events remain in place until the end of August, including full suspension of Australian sports and the cancellation of Euro 2020, the company said in a trading update.
In the past few days most major global sports have been suspended or cancelled.
The group said this would “obviously have a material impact” on its revenue and earnings.
Last year approximately 78pc of its revenues came from bets placed on global sporting events.
The company said quantifying the precise earnings impact was “difficult” at this point due to a lack of visibility on the duration of restrictions on sporting events.
While most sporting events have been cancelled, some are now being scheduled to take place behind closed doors on the back of the coronavirus.
These include some Australian sports as well as Irish and Australian horse racing.
Should horseracing be cancelled outright in Australia, Ireland and the UK, and the groups UK/Irish shops be closed, Flutter estimates that this would incrementally reduce group earnings before interest, taxation, depreciation, and amortisation (EBITDA) by approximately £30m per month.
Peter Jackson, Flutter Entertainment CEO, said: "The challenge currently facing our business and the industry more widely is unprecedented in modern times.
While our near-term profitability will be impacted by the essential measures being taken globally, the board will remain focused on protecting shareholder value and managing the business through these turbulent times."