Predicting a match-up on the pitch, when a team is as fluid in attack as Spain, can be futile. Attackers have notional starting positions but they switch seamlessly during the game, meaning defenders will not face the same player for long. Yet, over the course of the match, some patterns will emerge.
On Thursday, Spain's own defenders are unlikely to be bothered; the only question will be how long the Irish can hold their opponent off.
Against Italy, David Silva (left) started on the right side of attack, but exchanged position with Cesc Fabregas in the middle. Silva will again drift in from the right, dragging defenders in with him.
Although Ireland will line up bodies behind the ball, he — like much of the Spanish team — is adept at operating in tight spaces.
The Irish left-back Stephen Ward (right) did not look entirely convincing against Croatia's Darijo Srna the other night, and was at fault for the second goal.
He will be in for a hard time against Silva.
If he does track the Manchester City attacker, he risks leaving space for Alvaro Arbeloa to overlap. But at the same time, a failure to tackle Silva could leave the centre-back hopelessly exposed. It will be a desperate battle.
