The 32-year old spent his entire career in his homeland before moving to 'Boro from Celtic in January 2010 and says that moving to the Championship has helped improve his game because of the quality of competition.
He also said that the next goal was take another step up to the Premier League by gaining promotion with the Teessiders.
"Celtic was a great club and all that - but for me I'm playing at a higher standard now," Robson said.
"It's harder for me every week than it was when I was playing for Celtic.
"The Championship is one of the hardest leagues you will ever play in. Look at the teams in it - Cardiff have Bothroyd, Chopra and Bellamy, Leicester have Yakubu and Kamara.
"For me there are teams in the championship with the kind of player you don't get to play against every week in Scotland.
"I hoped I was going to be playing in the Premiership when I went to Middlesbrough, but it hasn't quite worked out like that. Hopefully next year we make a push."