Steve Clarke's side eased into the third round of the Capital One Cup with a professional 3-0 win made more eye-catching by the Burundi-born winger's stellar contribution.
The 20-year-old academy product, who left the war-ravaged African state with his family as a 10-year-old, was by far and away his side's stand-out performer as he took the game to the Welsh side from the first minute to effectively wrap up the win before the half-time whistle had even blown.
Clarke said of Berahino, who was included in Gareth Southgate's England Under-21 squad for their forthcoming qualifiers: "He's a born goalscorer and he's hungry to do well.
"He can play in any position in the front three, either in the middle or on either side. For us in this moment in time he is very useful.
"I'm absolutely delighted for the boy because he's worked so hard for his chance and he took it with both hands.
"You saw his performance here. In the first half he was the best player on the pitch. He tired a bit in the second half - as did a few others who haven't had much playing time recently.
"But he's given me a lot to think about and I'm really pleased he has."