Birmingham City claimed a goalless draw away to Portuguese side Nacional in the first leg of their Europa League play-off.
The Championship side, playing their first European game in 49 years, came closest in the first half when Steven Caldwell and Chris Wood both hit the woodwork.
Wood hit the post again just after the restart as the Blues continued to create chances.
Chris Hughton's side play the second leg at St. Andrews on Thursday, August 25.