Phil Thompson fears the situation surrounding Mamadou Sakho could have a disruptive influence on Liverpool.
The Reds had embarked on a four-match winning run, including a stunning comeback victory over Dortmund and a 4-0 thumping of rivals Everton, before it emerged on Saturday that UEFA were investigating an alleged anti-doping violation by the defender.
Jurgen Klopp's men then let a two-goal lead slip at home to Newcastle in the Premier League on Saturday, when the France international was left out of the squad at Anfield, although he has not been suspended either by Liverpool or UEFA.
Sakho apparently will not contest the result of his positive drug test and now faces the possibility of a ban if found guilty.
While acknowledging the defender's absence will be felt on the pitch, Thompson fears a greater problem exists in how the case affects the club ahead of their Europa League semi-final first-leg tie at Villarreal on Thursday.
He told Sky Sports: "I think the big thing for Liverpool as a whole is that it could be disruptive to all the positive vibes that have been around the team and you could do without it.
"It's taking the focus away from what has been achieved and Klopp has got to try and regroup the players in mind and body, but he's absolutely the right man for it."
Sakho and Dejan Lovren had established themselves as Klopp's first-choice centre-back pairing and Thommo is hoping that Martin Skrtel can fill the void left by Sakho.
"In footballing terms, Sakho will be a big miss," the Soccer Saturday pundit added. "He's had his ups and downs but I think everybody has responded to his passion and commitment when it comes to defending and his influence has been massive.
"It will be a big loss but I think it gives Skrtel a chance to get back in the side, potentially until the end of the season if it goes badly for Sakho."