Despite dominating for large parts of the NAB Challenge clash and having 10 more scoring shots than the Lions, Richmond just hung on for a 13.12 (85) to 11.4 (70) win at Gold Coast Stadium.
The Tigers were led by big guns Nathan Brown (three goals), Matthew Richardson (20 possessions, 13 marks) and Ben Cousins (25 touches).
The Lions relied on Daniel Bradshaw's five goals up forward but were wasteful entering the forward 50.
Richmond extended their lead for each of the first three terms before the Lions slammed on the first four of the last quarter to draw within six points.
Wallace admitted his team's poor conversion, which included a number of set shot misses from inside 40m, almost cost them.
"Every time you don't convert that keeps the game open," he said.
"Unfortunately we missed our easy opportunities and when they went forward they nailed theirs.
“It was similar to our game against Collingwood, we missed scoring opportunities in that game as well so the one thing we've really come away with we need to tidy up before round one is just our conversion rate.
"Most of them we thought were relatively kickable."
Wallace was happy with most of his team, including centre half back Luke McGuane who kept Lions captain Jonathan Brown to one goal, and saved special praise for Cousins.
In just his second game this season, the Brownlow medallist was superb, racking up possessions all over the ground.
"Obviously he's stepping up a bit each and every time he plays," Wallace said.
"I thought his tackle intensity was the better part of his game that lifted our rating early in the second quarter."
Wallace said he was unlikely to make many changes for round one.
Richmond 3.4 7.6 10.9 12.13 (85)
Brisbane Lions 3.1 5.2 6.4 11.4 (70)
GOALS
Richmond: Brown 3, Morton 2, Schulz 2, Cousins, Moore, Riewoldt, Bowden, Tuck.
Brisbane Lions: Bradshaw 5, Drummond 2, Brown, Dalziell, Johnstone, Stiller.
BEST
Richmond: Richardson, Schulz, Deledio, Cousins.
Brisbane Lions: Bradshaw, Drummond, Adcock, Power.
Injuries
Richmond: Foley (lower leg)
Brisbane Lions: Nil.
Umpires: S Grun M James S Wenn.
Crowd: 4369 at Carrara Stadium.
The views in this story are those of the author and not necessarily those of the clubs or the AFL.
