The 6ft 4in Denmark forward is wanted by Tony Mowbray to beef up his attack as he tries to move out of relegation trouble.
Target: Soren Larsen has had spells in Germany after failing to settle in France
Mowbray has limited funds for loans with Boro strapped for cash and is expecting to lose a few of his first-team squad, notably Jason Steele, David Wheater and Gary O'Neil, to Premier League suitors.
Larsen, 29, has a decent goalscoring record but has failed to settle in France after being signed to replace Johan Elmander and has had stints on loan in Germany.
Mowbray may also look at taking Jonathan Woodgate back on loan from Spurs, although Premier League clubs are also interested.
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Explore more:People: Tony Mowbray, Johan Elmander, Jonathan Woodgate, Gary O'Neil, David Wheater Places: France, Germany, Denmark