Major League Soccer and the MLS players union avoided the first work stoppage in league history, reaching an agreement in principle Wednesday evening on a new collective bargaining agreement, sources with knowledge of the talks told ESPN.

The story:

Pending formal ratification by the members of the MLSPU, the deal allows the 2015 regular season to begin on time, starting with Friday’s tilt between the Chicago Fire and reigning MLS Cup champions the LA Galaxy.

The new CBA concludes a difficult negotiating period that began in earnest last December, and ended just two days before the start of the regular season. The last three days in particular involved some intense negotiations, with Tuesday’s session lasting deep into the night, and not concluding until 6 a.m. on Wednesday morning.

Details have yet to be confirmed, but the deal is believed to contain the first provision for limited free agency in the league’s history.

An announcement is expected to be made later on Wednesday night, sources said.