And even though the tourists ran out comfortable winners in the fifth game of their 10-match tour, Dennis says he learnt some valuable lessons ahead of the opening international in Brisbane in seven days' time.
"I'll go back (on Sunday) and try and help the boys prepare for that first Test in Brisbane," said Dennis, who is convinced his 80-minute stint was just what he needed even though it has led to suggestions that he may miss out on selection for the opening rubber.
"I hadn't played for two weeks. Physically, it's good for my body, and I can pass on a bit of knowledge of how they play.
"The effort was there and we were keen to get into it, but we probably committed too tight and got shown up around the edges and off turnover ball, where they were very good.
"There's a few things that I can pass on there but preparation's already started in terms of how to manage that."
One area Dennis expects Deans and co to pay particular attention to this week is the contest at ruck time - a part of the Lions game that he admits caused his side problems in their 47-17 defeat.
"The ruck is going to be talked about this week. It's not so much a technical thing, it's just the emphasis they have around the park with or without the ball," added Dennis.
"The connection of how they keep you nice and tight around the forwards and, before you know it, they get you on the edges - the defensive focus on how to manage that and how to defend the width of field by keeping the eyes up and keeping it physical and getting off the line.
"We saw a few threats during the week in terms of preparation and what The Lions offered. There are always new things that they are going to throw at you. I am sure there are still a few things up their sleeves in terms of how they want to play that first Test."