Niko Kovac was relieved to fall on the right side of a penalty shoot-out "roulette" after Borussia Dortmund edged out Eintracht Frankfurt in the DFB-Pokal second round.

Dortmund battled to a 1-1 draw across 120 minutes as Julian Brandt cancelled out Ansgar Knauff's opener, before Eintracht forward Jonathan Burkardt saw an extra-time finish ruled out for offside.

Gregor Kobel, who impressed in regular time with a trio of fine stops, then saved Fares Chaibi's penalty after Ritsu Doan had fired over his spot-kick as Dortmund prevailed 4-2 on penalties.

Kovac was the Eintracht manager the last time these two sides met in the cup, with Dortmund winning the final 2-1 in 2017, and the former Croatia international was delighted to end up on the victorious side this time.

"The game couldn't have been decided any differently because both teams gave their all," Kovac said on Sky Sport Germany after Tuesday's victory.

"We're happy we advanced, but I also feel for Eintracht because I know how difficult it feels to be eliminated. It was so difficult for us because Eintracht were good.

"They had an advantage with the stadium and their fans, which they used well. But you don't have to celebrate in the cup; you just have to advance and give it your all.

"That's what the boys did from the first to the 120th minute. In the end, it's roulette."

Dortmund were indebted to the heroics of Kobel, who made six saves before the shoot-out win – his joint-most in any match across all competitions this season (also six against Bayern Munich).

"It was a tough game," Kobel said in the mixed zone. "The penalty takers did an extremely good job. When there's extra pressure on the bench after 120 minutes, it's not easy to shoot.

"Everyone really placed their shots very well. So it was a really great evening. It was the second round of the cup, but it felt like more.

"A game like that is just incredibly fun. We've really built up a bit, also in terms of the atmosphere.

"A win like that, and the one a few days ago against Cologne, are obviously very, very good – for the whole team, the atmosphere, the energy."