Stuck in Low Range!!!

Hi All, I put my 1991 200tdi 110 in low range yesterday on tarmac and just drove it forward a short distance. On trying to put it back into high the gear stick had a lot more play and moved very freely. It would not then go into high and is now stuck in low!!!
It moves freely without depressing the clutch and from my limited knowledge it appears that one of the two rods may be damaged. It drives fine in low any help or ideas before I start pulling things apart would be much appreciated!!
Cheers Mike

Hi Mikey, have you looked in the section common faults & questions.

Is it in diff lock too? Try reversing everything you did. Eg. if you drove forward and left, reverse hard left. You could also try lifting a wheel up onto something like a grass bank.