ZURICH: Players who switch clubs during the course of a season will be allowed to play for both in the Champions League under new rules announced by UEFA on Tuesday.

The European global soccer body said in a statement that it would also allow teams to use a fourth substitute in extra-time during Champions League and Europa League knockout ties.

These can include one player who has represented a different club in the Europa League group stages but none who have been fielded for another club in the Champions League group stage.

The present ruling prevents Barcelona from fielding Philippe Coutinho in the Champions League this season as he has already played for Liverpool.

Alexis Sanchez was eligible for Manchester United, however, as he switched from Arsenal in the Europa League to the Champions League.

The new rules state that “that a club may register three new eligible players without any restrictions.”

UEFA said the new ruling brought it into line with domestic leagues which “do not impose restrictions on the eligibility for competitions of players registered for a new club during the winter transfer window.”

It said that 23 players, instead of 18, would be allowed on team sheets for the Champions League and Europa League finals, and the European Super Cup match.