Borussia Dortmund 1 Liverpool 1

Liverpool's "little" advantage, Jurgen Klopp had claimed, lay in the knowledge his revival of Borussia Dortmund began with the beating of favourites. Klopp will not proclaim that process is underway with his new club just yet but they took a significant step towards the Europa League semi-finals with a dogged draw and precious away goal at the Westfalenstadion.

Dortmund had been consumed by Klopp's return and he gave them a painful reminder of his ingenuity by starting Divock Origi in place of Daniel Sturridge. The young Belgium international stunned the home crowd with the opening goal, one that could prove crucial in the second leg at Anfield next week, and a relentless, committed display that encapsulated the contribution of the entire visiting team. Mamadou Sakho stood tall and commanding against Dortmund's much-vaunted attack and, for all the pre-match talk of facing the favourites, Liverpool left Germany knowing there is little to fear from Thomas Tuchel's players.

Klopp strolled back out at the Westfalenstadion 35 minutes before kick off, giving a polite little wave to the Yellow Wall and studying his former players intently as they went through their warm-up before attention turned towards his current charges. There, Sturridge trained among the substitutes having paid the price for a subdued display against Tottenham Hotspur on Saturday and his manager’s preference for the movement and physicality of Origi.

Even with the requirements of the contest taken into account it represented a major call to start a raw 20-year-old over the team’s leading striker and a reminder to Sturridge of where he stands under Klopp. Wherever his manager tells him to, basically, and the selection was vindicated by Origi’s first European goal for the club.

The Liverpool manager also made a tactical decision to combat Dortmund's creativity in central midfield by switching James Milner to the left of a central three. Alongside Emre Can and Jordan Henderson, Milner added strength and stability to the visitors' performance as they absorbed pressure but the talents of Henrikh Mkhitaryan and Julian Weigl could not be suppressed completely. The pair's influence increased in tandem with the home side's control over the quarter-final first leg, though it was not reflected on the scoresheet.

Tuchel's team made an edgy start, with loose passes and careless first touches indicating the distraction of Klopp had got to them and undermining attempts to seize the initiative. Maybe it was only a coincidence that the biggest culprits, Lukasz Piszczek and Erik Durm, were the two players in yellow closest to their former manager in the first half as they patrolled the flank in front of the technical areas. Gradually, however, Dortmund's quality pressed Liverpool back and it required two crucial interceptions from Sakho to prevent the German side taking the lead.

Dortmund's early attacks had been overelaborate, Mkhitaryan taking a heavy touch in front of Simon Mignolet's goal for example when Mats Hummels sent over an inviting cross from the left, but the threat grew. Weigl, the impressive 20-year-old midfielder, released Marcel Schmelzer behind the Liverpool defence with a sweeping pass over the top. The left-back controlled and cut the ball back for Mkhitaryan but, with the goal at the mercy of the Armenian and his shot destined for Mignolet's net, Sakho stretched out one of his telescopic legs and diverted the danger. The French central defender repeated the trick when Pierre-Emerick Aubameyang broke down the left and attempted to find Marco Reus unmarked in front of goal until Sakho intervened again.

The pressure intensified, the game flowed in one direction. Aubameyang had a free-kick deflected just wide, Mkhitaryan went close and Mignolet saved comfortably from the Gabon international. And with Dortmund dominant, Liverpool struck. A cross from the left was headed on by Milner. Origi read the midfielder’s intentions quicker than any home defender and pounced on the ball, held off Piszczek on the edge of the area and steered a low shot back across goal and inside Roman Weidenfeller’s right hand post. Klopp fist-pumped the one corner of the Westfalenstadion that did not fall silent.

Dortmund descended from control to chaos in an instant and only last-ditch defending prevented Nathaniel Clyne and Milner doubling Liverpool's lead moments later. Origi should have done so with the last kick of the half when played through the home side's suspect defence by Alberto Moreno, but his attempted chip was too close to Weidenfeller, who made a vital save.

Moreno did not hide his disgust at the missed opportunity and his instinct proved correct moments after the restart.

Liverpool had delivered a disciplined away display, making Dortmund's equaliser all the more galling. The visitors switched off at a short corner and gave Mkhitaryan freedom to sweep a left-footed cross into their penalty area. The imperious Hummels towered above Adam Lallana to steer a header beyond Mignolet's grasp.

Klopp's team were stung into a response and Weidenfeller was forced to make excellent saves from Philippe Coutinho, Clyne and Coutinho again as Liverpool unnerved the German defence frequently. Dortmund's vulnerability at the back offers further encouragement for Liverpool at Anfield next week.