Video assistant referees (VAR) will be used at the Nations League finals, Uefa has confirmed.
The technology will be used in England’s semi-final against Netherlands on Thursday following a successful trial in the Champions League knockout stages.
The Nations League starts on Wednesday when hosts Portugal play Switzerland in the other semi-final. The final and the third-place play-off are on Sunday.
England manager Gareth Southgate, and coaches from the other four nations, were briefed in April by Uefa referee chief Roberto Rosetti on how VAR will work.
The technology will be check for "clear and obvious errors" in relation to goals, mistaken identify, red cards and penalty incidents.
Southgate said: “We had a good briefing in Porto recently and had positive experiences of VAR in the World Cup.
"My feeling both internationally and domestically is that, in the main, the big decisions have been right.
“The purpose of using VAR is to help the referees so I think it has been a help. You will never get a system that is 100 per cent fail-safe but the key decisions that are clear and obvious have been rectified. For me, that is a positive.”
Netherlands head coach Ronald Koeman said: “VAR is a good help to make football fairer and most of the mistakes will be corrected. That of course is a good thing.
"We must realise, however, that discussions will continue to exist, because you can often interpret actions in multiple ways.
"I am in favour of the VAR tackling the big, obvious issues only, rather than to search endlessly for potential errors.