Liverpool manager Juergen Klopp knows all about heroic comebacks in European competition but even their barnstorming fightback against Barcelona in the 2019 Champions League will not prepare them for Thursday's task in Atalanta.

Klopp's side suffered a resounding 3-0 home loss in the first leg of their Europa League quarter-final and travel to Italy with a mountain to climb.
While they also trailed Barcelona by a 3-0 scoreline in the Champions League semi-final five years ago, their 4-0 victory in the return fixture came with the noisy backing of a vociferous home crowd, while Thursday's atmosphere will be very different.
"The result is similar definitely. The performance not really," the German coach told reporters on Wednesday. "We lost 3-0 in Barcelona and people didn't know how, now we lost 3-0 at home and are away, it's a massive difference. We are here and will try to win the game, that's all. That's what we should do.
"(Last week) we had really good moments but they completely deserved to win. Let's start with a much better performance and try to win the game and we will see how much time is left at the end."
The Liverpool boss does have experience of losing at home to Atalanta and winning by a big margin away after the sides met in the 2020 Champions League group stage, when his team beat the Italians 5-0 in their own stadium before suffering a 2-0 home defeat weeks later.
"We played four years ago against Atalanta. Tomorrow the game is more difficult as they don't have to score at all. Not sure what they're going to do. It's not easy when you're 3-0 up.
"We won 5-0 here, we lost 2-0 in the home game. We will see who deals better with the situation. If Atalanta go through then they deserve it, if not then something special has happened."
While Klopp fired his players up with a rousing team talk before their victory over Barcelona, the German said he had yet to think about what he might say on Thursday.
"I will think about the speech tomorrow. I remember saying if we fail, let's fail in the most beautiful way and I'll say that again," he said. "A lot of supporters thought that was it after the (first) leg but now less people think it is decided. We are here, let's see."