Sounders FC will kick off yet another U.S. Open Cup title defense May 29 and learned its potential opponents for that first step on Wednesday.

Seattle, aiming for an unprecedented fourth straight championship, enters the field in the third round and will face the winner of a May 22 second-round match between the Georgia Revolution of the NPSL and the Atlanta Silverbacks of the NASL.

The Sounders would host the Revolution (Starfire Stadium in Tukwila at 7 p.m.) but would have to visit the Silverbacks (at Atlanta Silverbacks Park at 4:30 p.m.).

Potential fourth-round matchups will be announced at a later date.

The Sounders have played their past seven Open Cup games at home as beneficiaries of a closed-envelope bidding process. U.S. Soccer changed to a random selection process this year until the semifinals, provided teams apply to host and have home venues that meet tournament standards.

Seattle's last Open Cup game on the road was in the third round against Portland in 2010.

Last year, the Sounders became the fourth team in the tournament's 98-year history to win three in a row.

Joshua Mayers: 206-464-3184 or jmayers@seattletimes.com