Trent Alexander-Arnold has handed Liverpool a major scare - and could face a race against time to be available for Sunday’s visit of Manchester City.
Alexander-Arnold was not part of the Reds’ squad that flew to Porto on Monday ahead of their Champions League Group B clash on Tuesday evening.
The right-back had taken part in open training at Kirkby earlier in the day only to not be among the party that disembarked the team coach at their hotel in the evening.
Liverpool have remained tight-lipped over Alexander-Arnold’s fitness.
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But the defender must be considered a doubt for the blockbusting Anfield showdown against champions City this weekend.
Wales international right-back Neco Williams, sidelined for the past month through injury, is fit again and was part of the 22-man travelling squad.
Jurgen Klopp could also turn to James Milner - who deputised for the ill Alexander-Arnold against Crystal Palace earlier this month - in the right-back role.
Joe Gomez is another alternative for the position.
Klopp is already without Harvey Elliott and Thiago Alcantara for the Porto clash, although Naby Keita is available having missed Saturday’s 3-3 draw at Brentford.
Liverpool top Group B having beaten AC Milan at home 3-2 on the first matchday. Porto secured a goalless draw at Atletico Madrid.
