Roman Weidenfeller the Hero as Borussia Dortmund Escape Union Berlin Disaster

Life as a back-up goalkeeper can be tough. Having to function when you are so rarely called upon takes a strong mentality. That is especially true for someone like Roman Weidenfeller, who spent most of his career as a clear-cut first-choice 'keeper.

Of course, Old Father Time catches up to us all and Weidenfeller, at 36 years of age by far the oldest player in Borussia Dortmund's squad, has long accepted his role as an elder statesman on a team with so many young talents who need someone in the locker room to offer guidance.

Still, it must have been mighty sweet for the 2014 FIFA World Cup winner to have one more night in the spotlight. Weidenfeller made two saves in the penalty shootout against Union Berlin on Wednesday, keeping his side alive in the DFB-Pokal after a hard day's work.

He wanted to exude calmness and signal to his team-mates that they would somehow make it through, the veteran told German broadcaster Sky after the match. Though not known as a penalty killer, he added, he has saved a few important ones in his career.

With that, of course, he reminded of his save against Arjen Robben in a decisive Bundesliga match against Bayern Munich in 2012. Unlike the Dutchman's rather weak effort, however, his first penalty save on Wednesday required a full stretch and quick reaction. Every time a 'keeper keeps a penalty out it is a strong moment, but this time, it was actually a brilliant save to boot.

His second save was, in comparison, almost easy, as Stephan Furstner put it at the ideal height for Weidenfeller to parry. Union's third and final taker Philipp Hosiner tried to take the 36-year-old out of the equation with a high shot but smacked the crossbar.

Weidenfeller was the hero of the night, receiving praise from his team-mates and a special reception in front of the famous Sudtribune, where the club's most loyal fans watch the game, long after the final whistle:

He must have felt some sense of a special satisfaction, seeing as it was in the DFB-Pokal where he lost his status as the No. 1 goalkeeper under Jurgen Klopp. It was not by accident that Weidenfeller mentioned his 15-year-long attachment to the club to Sky after the match.

Given his age and contract status—his deal is up after this season—it is entirely possible that this was Weidenfeller's last big hurrah, even though he is set to stay in goal throughout the cup campaign.

That it came this far against Union is a problem in and of itself, of course. Dortmund did not exactly cover themselves in glory, Weidenfeller told Sky.

His head coach Thomas Tuchel said in his press conference: "It was a long match, a hard fight. We probably won in the end thanks to our stubbornness, our desire, our dogged belief that we would win no matter what and our spectators. Nobody can claim that the team didn't give everything tonight."

Indeed, the resiliency in the team should not be questioned, but that cannot gloss over the fact that the Black and Yellows are now winless in five domestic games—wins on penalties count as draws in the record books.

Much like in most games over the last few weeks, the personnel situation has to be considered as a mitigating circumstance. Adding to the already missing team captain Marcel Schmelzer, midfielder Raphael Guerreiro and attackers Andre Schurrle and Marco Reus, star striker Pierre-Emerick Aubameyang was unable to play after picking up knocks in a 3-3 draw against FC Ingolstadt on the weekend.

Christian Pulisic missed the cup tilt with an illness, while defender Marc Bartra has not fully overcome adductor problems. It left Tuchel with another starting XI that has never and probably will never again play in this constellation.

Nuri Sahin replaced Julian Weigl in defensive midfield for his first run-out of the campaign, but it was overshadowed by a senior debut for 18-year-old winger Jacob Bruun Larsen.

The Dane had never even made the squad in a competitive match to this point, but, with Pulisic out and Ousmane Dembele also affected by illness during the week, he was the only option seeing as Dortmund wanted to stick to their system with two true wingers.

The moment was never going to be too big for Larsen, who played for his country at the Rio Olympics in the summer, but it was still a big call from Tuchel. Larsen, deployed on the right wing, repaid that confidence with a courageous performance. Not everything came off, far from it, but he kept attacking his opponents and even brought the first goal.

It will go down as an own goal for former Dortmund man Michael Parensen, but Larsen earned it with another spirited run and an attempt to create something when his team needed a spark going forward.

Despite a strong showing from both Mario Gotze and Gonzalo Castro in midfield, the Ruhr side struggled to move the ball into dangerous zones. Left-winger Emre Mor was incredibly inaccurate for large stretches, while back-up striker Adrian Ramos failed to make himself available for combinations around the box.

Sport magazine Kicker (link in German) counted 29 shots for the hosts, but real scoring chances were few and far between among that number. "It was a complicated match because we missed out on the chance to get the second goal, to score earlier," Tuchel said in his press conference, but, apart from a Mor attempt that hit the post three minutes from the end of regulation, one struggles to identify exactly which chance the 43-year-old referenced.

Of course, Union had even fewer attempts and needed a brilliant goal from substitute Steven Skrzybski to make it to extra time, but the 2. Bundesliga side deserve a lot of credit for a confident showing in front of almost 80,000 spectators. The fans of Iron Union, as the club from east Berlin are largely known, contributed to a raucous atmosphere that set a worthy stage for a vintage night in the cup.

Dortmund, however, could have done without that night extending for 30 minutes. The Revierderby against arch-rivals Schalke 04 on Saturday looms large, and a number of players will feel extra time in their legs.

Tuchel decided to view the positives:

It helped us more than it harmed us. It is clear that we will need to give absolutely everything we physically have to give in order to get the result that we want on Saturday evening. It was a good lesson, a good experience to see that it is always worth fighting, giving everything for each other and not stopping, no matter how many things go wrong.

It may well be a case of calculated optimism, although Dortmund could receive a welcome personnel boost on the weekend. Aubameyang, Bartra and Pulisic could return, while Tuchel expects Guerreiro and Schurrle in team training ahead of the match.

Weidenfeller, Wednesday's hero, will not be on the pitch against Schalke, but he had his indelible moment. There are few more deserving of such a highlight late in a fantastic career than him.

Lars Pollmann also writes for The Yellow Wall. You can follow him on Twitter.