Alex Wilkinson played a full match for Jeonbuk which had not lost at home on the continent this year ahead of the meeting with the Japanese treble winner.
Jeonbuk attacked for long periods but could not find a way past the Gamba defence, wasting some scoring chances in the process.
The 2006 ACL champion extended that record in a match the K-League Classic side dominated for long spells without being able to find the crucial opening.
Gamba, too, has had a fine recent record in the Champions League and some stout defending saw the 2008 champion take its run of unbeaten games on the continent to seven ahead of the return meeting with Jeonbuk at Expo '70 Stadium in Osaka on 16 September.
