I honestly don't see the grounds for confusion, and neither do i understand why the decision is supposedly nonsensical.
The rules:
A player in an offside position receiving the ball from an opponent who deliberately played* the ball, including by deliberate handball, is not considered to have gained an advantage, unless it was a deliberate save by any opponent.
*‘Deliberate play’ (excluding deliberate handball) is when a player has control of the ball with the possibility of:
- passing the ball to a team-mate;
- gaining possession of the ball; or
- clearing the ball (e.g. by kicking or heading it)
If the pass, attempt to gain possession or clearance by the player in control of the ball is inaccurate or unsuccessful, this does not negate the fact that the player ‘deliberately played’ the ball.
The following criteria should be used, as appropriate, as indicators that a player was in control of the ball and, as a result, can be considered to have ‘deliberately played’ the ball:
- The ball travelled from distance and the player had a clear view of it
- The ball was not moving quickly
- The direction of the ball was not unexpected
- The player had time to coordinate their body movement, i.e. it was not a case of instinctive stretching or jumping, or a movement that achieved limited contact/control
- A ball moving on the ground is easier to play than a ball in the air
The situation: Beto is trying to put pressure on Arsenal in their build up on the half way line, Gabriel is running out of options and Beto is approaching fast. Gabriel tries to play the ball out wide and Beto instantly sticks out a leg hoping to block the pass and gain control for a counter. Ball goes via Beto to a offside placed Nketiah who passes it to Viera and then onwards to Martinelli who scores.
Considering the proximity to Gabriel when he attempts the pass, time he has to think, i think it's fairly straightforward to conclude that Beto's action is well outside the realm of deliberately playing the ball, and that it would be extremely harsh to consider Nketiah as onside simply because Beto tried to make an instinctive block on the half way line when the ball is being played in a completely different direction than towards Nketiah.
Offside should be the outcome in 10/10 similar situations.
Beto didn’t play Nketiah offside, he just didn’t play him onside…