Rio Ngumoha was excluded from Liverpool’s traveling squad for the Champions League game against PSV Eindhoven on Wednesday as UEFA rules prevented him being registered for the match.

The 16-year-old made his senior debut last month in the FA Cup win over Accrington Stanley when he became the youngest player to ever start for Liverpool. He impressed Arne Slot with his performance against the League Two club and is among the most exciting talents emerging from Liverpool’s Kirkby academy .

That was on show again on Tuesday ahead of the PSV game, with eight previously untested youngsters among the group that trained as part of the open session. And a number of them were included in Slot's rotated squad for the game, with the likes of Mohamed Salah and Virgil van Dijk left at home.

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Jayden Danns and Trey Nyoni, who have already played for the first team this season, made the cut alongside Kieran Morrison, Isaac Mabaya, Trent Kone-Doherty, Amara Nallo and James Norris,

It would have been the perfect opportunity for Ngumoha to feature but he could not be included. The youngster was not registered at the start of the season among the Champions League List A squad, a category for players born before 1 January 2003.

UEFA rules state players born on, or after 1 January 2003, can join the List B and therefore be registered to play in Champions League games, so long as they have been at the club for at least two years. Conor Bradley, Harvey Elliott and Jarell Quansah are examples of such players and did not need to be included in the List A squad earlier this season.

However, with Ngumoha only joining Liverpool from Chelsea last summer, he does fit into the category. The attacker could be added to the List A players for the knockout stages, an option taken on Amara Nallo and Trey Nyoni ahead of the group stage, despite both being born after 1 January 2003.

Joe Gomez was not included after he returned to training on Tuesday. The defender hasn’t played this calendar year after picking up an injury against West Ham United at the end of December.

Liverpool heads to PSV knowing it only needs a point to secure top spot in the Champions League after winning all seven of its previous games this season. A defeat will even be enough on what looks set to be a frantic final day of the league phase, should Barcelona fail to beat Atalanta.

The Reds secured passage to the last-16, bypassing the play-offs in the process, thanks to last week’s win over Lille. Liverpool will definitely finish in the top two no matter what happens on Wednesday night.