Brighton striker Aaron Connolly has joined on loan until the end of the season.
The 21-year-old Republic of Ireland international has completed his move to Teesside, despite strong interest from elsewhere.
Indeed, Middlesbrough boss Chris Wilder has explained his reasoning behind the signing,
Speaking to the club’s website, Wilder said: “I’m delighted. It’s an area of the pitch we need to improve in terms of competition for places.
“He’s a young player, he’s played in the Premier League a number of times, and he’s from a technical football club. He’s also played for his country.
“He gives us pace, can finish at the top of the pitch and gives us competition for the players around him.”
Connelly had made 45 Premier League appearances over five seasons with the Seagulls, netting five times in the process.
The Oranmore-born player has also featured eight times for the Republic of Ireland.