But come Friday and in what is sure to be a red-hot atmosphere at Stradey Park, Wallace, who was a rock in the Munster side that swept to European glory last season, will be doing everything in his power to prevent his international colleague from ruling the breakdown battle.
The first of the Heineken Cup quarter-finals has been sold-out for weeks and Limerick man Wallace has acknowledged just how big a part Easterby plays for his club and country.
"Simon is such an unsung hero and is in the form of his life at the moment, so stopping him doing what he does best will be crucial to our chances of winning," said the 37 times-capped flanker.
"He will be trying to get into our faces from the start - something he does so well - and you can imagine just how much he will relish doing that.
"Simon was outstanding in the Six Nations and just seems to get better and better. While he will certainly be passing on a few tips about us to the Scarlets players, we also know all about him as a player as well. So it certainly promises to be an interesting battle on Friday night."
Wallace hit the half century mark in the Heineken Cup last December when he lined out against Cardiff. The experienced openside has started Munster's last 14 European games and is crucial to their chances of success in Llanelli.
While there is sure to be plenty of banter on the pitch on Friday, Wallace revealed he and Easterby have already "had a few words about it. It will all be friendly stuff until we get out on the pitch.
"Then it will change as both teams will be going full pelt at each other in what is going to be just a massive game," he added.