BOSTON (AP) -- Daily fantasy sports rivals DraftKings and FanDuel have agreed to merge after months of speculation and increasing regulatory scrutiny.

The two companies made the announcement Friday but didn't release financial terms. The deal isn't expected to be finalized until later in 2017 and still requires federal approval.

Industry experts say the merger will likely raise anti-trust concerns with regulators since the companies control nearly 90 percent of the market.

Company officials say the merger will help cut costs as the two fight to remain legal in states across the country.

 Daily fantasy sports competitions are online games in which players pick teams of real life athletes and vie for prizes based on how those athletes perform in actual games.

 But state regulators have questioned whether the competitions amount to illegal sports betting.