Sky Sports has confirmed that Arsenal defender Calum Chambers will leave the club to join Middlesbrough on a season-long loan deal.
The 21-year-old started the first official game of the season against Liverpool in a game that saw the Reds battle past the Gunners by 4-3.
Sky believes the Englishman could make his official debut for Karanka's side on September 10 against Crystal Palace.
A photo posted on Twitter by Keith Downie shows the defender on his way to his Middlesbrough medical.
In May, the youngster made it clear that his objective this season is to enjoy regular first-team football.
"For me, I just want to play games, so, yeah, that's it for me," he said before pre-season.
"But at the moment I am not thinking too much about next season, I just want to go and enjoy my summer. Then we'll get back at it soon."