The 22-year-old Scot could not hide his delight after firing his side into a 2-0 lead over Reading on Saturday to open his account in the English top flight.
But for the third time in his 13-month spell on Wearside, he celebrated by removing his shirt and was promptly booked by referee Steve Tanner.
The Irishman was relaxed about the former Celtic winger's latest misdemeanour after the game on a day when FA Cup hero Ian Porterfield was commemorated in poignant style.
However, Wallace is expecting to be hit in the pocket after failing to keep his emotions in check.
He said: "It was nice to get my first Premier League goal - a special moment and it turned out to be an important goal.
"I will probably get a fine for taking my shirt off, but it's worth it. Hopefully the gaffer agrees.
"I don't know why I do it. I don't plan it, it just happens. It won't happen again - the gaffer will probably make sure.
"He hasn't said anything to me about it, maybe in training this week. He will just dock my wages instead."
"That's how we need to perform, and hopefully we can keep that going at Boro.
"It's important that we get an unbeaten run together."