The England U21 forward announced his arrival at Old Trafford on Saturday, netting the winner against Manchester United - as part of an all-round impressive display.
Soon after, news emerged that the 20-year-old's current £850-per-week deal is set to expire in the summer.
So, what do we know about the United slayer? Here's five things we can tell you:
1) Berahino fled Burundi with his family in 2003, at the age of 10, during the east African country's civil war. His family was eventually granted asylum in Birmingham - where he joined West Brom's Centre of Excellence.
2) The forward spent seven years working his way up the club's youth ranks before signing a one-year professional contract in 2011.
3) Berahino was sent out on loan to Peterborough, Brentford and Northampton where he netted 12 goals in 33 loan appearances. He put pen to paper on a new two-year deal at the Hawthorns in January 2012.
4) The striker's Twitter following has risen steadily since his superb display at Old Trafford on Saturday afternoon. The player's verified account, @SBerahino has just under 10,000 followers.
5) Berahino has represented England at every level since the U16s. He scored on his debut for the U21s and grabbed an equaliser in England's draw against Finland.
What are your thoughts on Berahino?
image: © Catherine Kõrtsmik