Middlesbrough new boy Lee Dong-Gook was back on Teesside today after receiving a visa to complete the formalities of his move to the Premiership.The 27-year-old South Korea international striker trained this morning following his return from the Far East as his team-mates prepared for tonight's visit to Portsmouth. Lee signed an 18-month contract last week after being awarded a work permit, but had to return home immediately to secure the remaining documentation. Manager Gareth Southgate will now have to decide whether or not he is ready to be included in the squad for Saturday's league clash with Arsenal at the Riverside Stadium. Southgate told the club's official website: 'It's just a case of whether we involve him on Saturday as he will have done a lot of travelling. 'We will have to look at him physically and see how everyone else is as well. 'He looks sharp enough in training, but it was the close season over there and his basic fitness is down a little bit on what he would like. 'But he did not look too far behind. He did all the fitness tests and the results were very, very good. 'I played against South Korea four years ago and they were very fit, so I do not think fitness will be a big issue. 'But the two long flights he has had and the week without training might put him back a few days.' Lee, however, cannot wait to get started. He said: 'People in South Korea will want to hear that I am scoring goals, so that's what I hope to do. 'I am happy to finally get the chance to play in the Premier League.'