Hull left it late to book their place in the play-offs of Europe's second-tier competition in their first ever continental campaign.
An 80th-minute Sone Aluko goal was required to give Hull a 2-1 aggregate win over Trencin of Slovakia in the third qualifying round, and they now meet a Lokeren side who have won three of their last four matches.
Bruce told Hull's official website: "Lokeren are a very, very good side from what I've seen of them.
"And as we know, Belgium is producing some very good players. It will be a difficult game for us.
"As I've said, I'll be changing my team around and giving the players who got us into Europe, the chance to play in Europe.
"I think working it that way is what gives us the spirit that we're playing with. They're all going to get their chance.
"I had to leave people off the bench at QPR on Saturday. George Boyd in particular, who have [has] done wonders for me."
Robert Snodgrass (knee) will miss out for Hull while defenders Alex Bruce and Liam Rosenior are doubtful with back injuries.
