Macros for arenas

Hi,

I'm new on the server and I tried to write some macros for example sapping using arena1,2 and 3. Here is the kind of thing I wrote:
/cast [mod:ctrl,target=arena2] Blind.

But it doesn't seem to work in the few skirmishes I tried. Is there someone else who tried it and is having the same problem?

Thanks in advance for your answers.

Macguir

Edit: Strangely, when I use a macro to put focus (with the same modifier), it works and I can just blind focus. Anyway, if someone has an answer to it, would be greatly appreciated.