If you press them both at the same time do you tackle harder? Like when you push X down harder it makes your player go in harder...
Try and outsmart me, will ya?!
Eh? Erm? Err? You sure about that... :)
And I always slide tackle when the opposing player knocks th ball ahead, and not when he has it in close control.
If you keep hold of it, the player automatically pressures the person he's trying to tackle, but hold it too long and from behind and the ref blows for a foul 8/10 times.
So instead, what you need to do is anticipate the direction of the opponent's next move and intercept it either by simply running into the ball, or pressing 'X'.
Sliding tackles using 'O' demand better timing, so what you should do is to once again anticipate the player's next move and slide slightly before.
It's all in the anticipation.