Toulouse find themselves faced with a daunting trip to the Aviva Stadium later this month with a place in the final in Cardiff at stake and Bru, who himself twice lifted the European Cup, was impressed with what he saw from Leinster in their victory over Leicester last weekend.
"It was a really impressive game and Leinster and showed against Leicester what they can do," he said.
"They were impressive in terms of their speed and their intensity at the ruck and at the contest area and they have a lot of talent in their team.
"Last season we were European champions after playing all of the knockout stages in France but now we'll be playing on foreign territory.
"It's a huge challenge but it is very exciting."