So, as we all know you tend to meet the same people when you play arena above 1800.
1800-1900 same people 1900-2000 same etc.
A nice tip to know if you're meeting the same guys, thus setting your strategy real clear before is to remember their names and server. Making a macro.
So you have randomserver-randomname
Then make a macro doing /ignore randomserver-randomname.
If it's not him, you're getting player not found - if it is you get player ignored;
Now you know who you're up against before you start.
Make a bar and put all the different macros on it, you'll be having like 20 of them. :-)
Killblade added, to clear it even more up why you would gain an advantage by doing this.
"Its not that complicated, your not ignoring the players for the fact to 'ignore' them, but your just doing it to see if it is possible. If in fact you DO ignore them than that means they are IN YOUR ARENA and you can switch poisons / buffs etc... or whatever is necessary to beat that team."