Alexis Sanchez has unsurprisingly been named in Arsenal's squad for the group stages of the 2017-18 Europa League. However, such an inclusion would not mean that he is cup-tied for the Champions League in the event that he completes a January switch to Manchester City and Pep Guardiola's side advance to the knockout stages of Europe's elite club competition.
As per Uefa rules, teams that qualify for the last 16 of the Champions League can register a maximum of three new players to their squads before midnight on 1 February.
Any of these players can have featured in the qualifying rounds of either continental competition, although only one can have played in the group stages of the Europa League.
Obviously no player can represent two different clubs in the Champions League proper in the same season.
Contract rebel Sanchez has entered the final year of his current deal at the Emirates Stadium and had hoped to secure a summer reunion with former Barcelona boss Pep Guardiola.
Manchester City were reported to have finally seen a £60m ($78m) offer for his services accepted on transfer deadline day, only for the deal to collapse at the 11th hour due to Arsenal's failure to complete the signing of AS Monaco midfielder Thomas Lemar.
Arsene Wenger has led calls for the January window to be scrapped amid reports that City will return for Sanchez again in the New Year. The 28-year-old made his first appearance of the season in a 4-0 drubbing at Liverpool on 27 August after his return from a post-Confederations Cup break was delayed by a combination of illness and an abdominal strain.
Sanchez, who can start talking to overseas suitors in just four months time, played 90 minutes for Chile during their heavy World Cup qualifying defeat to Paraguay last week and is expected to start against Bolivia in La Paz on Tuesday night (5 September,) despite fears that he had suffered an ankle injury in training over the weekend.
Joining Sanchez in a rather youthful-looking 39-man Europa League squad are Jack Wilshere and Mathieu Debuchy, two more players who were heavily linked with moves away from north London before the transfer deadline.
2000 Uefa Cup finalists Arsenal, whose fifth-place Premier League finish in 2016-17 meant they missed out on a Champions League berth for the first time in 21 years, begin their Group H campaign at home to Cologne on 14 September before facing Belarusian champions BATE Borisov and former European Cup winners Red Star Belgrade on the road in September and October.
City's Champions League group, meanwhile, is comprised of Shakhtar Donetsk, Napoli and Feyenoord.