Liverpool's miracle comeback stuns Borussia Dortmund in Europa League (Video)

Until late on, it never really did look like Liverpool stood a chance.

Borussia Dortmund is one of the best teams in the world, after all. Top-five perhaps. The only reason Dortmund is in the Europa League at all is its fluky and injury-plagued, seventh-placed Bundesliga finish last season, Jurgen Klopp's final campaign in charge. But under Thomas Tuchel all has been set right. And when his men in yellow went ahead 3-1 at Anfield in the 57th minute of Thursday's seven-goal thriller at Anfield, it seemed like Liverpool's European campaign was over, because of away goals.

[ Liverpool vs. Dortmund stats | Europa League scoreboard ]

Yet somehow, courtesy of headed goals by the side's much-criticized center backs Mamadou Sakho and Dejan Lovren, late on and in extra time, Liverpool would drag it out 4-3 and advance to the semifinals by a 5-4 aggregate score. It was reminiscent of the 2005 Champions League final in which Liverpool overcame a three-goal, halftime deficit against AC Milan in Istanbul.

This quarterfinals second leg was immense fun, and it really had no right to be this close.

Because in the fourth minute, Dortmund stormed away on a counter. Simon Mignolet saved on Pierre-Emerick Aubameyang's volley, but then Henrik Mkhitaryan slotted home the rebound.

And five minutes later, Aubameyang did score on Marco Reus's slide-rule through ball, which the Gabonese popped into the near top corner, essentially ending the game. Or so it seemed.

Because even when Emre Can sent Divock Origi through just after halftime to get the Belgian on the scoresheet, the Reds needed two more goals.

And before Liverpool got another, Reus would sneak in behind and slot home on a surgical finish before the hour. Liverpool now needed three.

So Philippe Coutinho's fine curler from the edge of the box in the 66th minute didn't appear to be particularly consequential, since Liverpool was still two goals from advancing.

But then, in the 77th minute, Sakho nodded in on a bouncing corner. To make it 3-3 and 4-4 on aggregate.

Liverpool needed just one more.

Finally and incredibly, Lovren headed home on James Milner's injury-time cross to unloose pandemonium.

A good one for the neutrals, as they say.

Yet for all the uplifting emotion, there was something to else take away from it for the Liverpool fans. Because it demonstrated once more that the Reds are on something of an identifiable trajectory under Klopp, who took over from the finally-fired Brendan Rodgers in October. And that's something the club hasn't had in a long time.

It was obvious right away that his rebuilding project would take time – several seasons, at least – to take hold and will probably require several years more to restore Liverpool to its perch atop the global game, if it will ever get there again.

But if Liverpool isn't currently much closer to winning the Premier League or Champions League again – as it did 11 and four times, respectively, in the 1970s and 80s – Klopp's zippy tactics and savvy game plans at least promise the framework for future success, if it doesn't come in the Europa League this year. Cathartic wins over Manchester United in this competition and Manchester City in the league have set down a blueprint. And in Adam Lallana, Origi, Can and Coutinho, Klopp has unearthed or reinvigorated some useful pieces for his foundation.

Progress. Forward momentum. That's what Liverpool will have gotten from this Europa League campaign, no matter where it strands. And considering the depths the club had sunk to of late – the miraculous 2013-14 title challenge excepted – that won't be such a bad outcome whatever happens next.

And really anything could happen next.