The Stuttgart captain opened the scoring in the 29th minute, helping Sebastian Hoeness' side secure their second consecutive victory in the competition.
Undav admitted that finding the net again was a relief after going seven or eight matches without a goal.
"Of course it's a relief. As I said, it's always nice to score. To score again after a drought of, I think, seven or eight games feels good," he told DAZN.
However, the Germany international made it clear that ending his barren run was secondary to collecting three points.
"But ultimately, the important thing is that we won. That's the most important thing. I'm a team player, and I've said that before. As long as we're winning games, I don't have to score."
The striker also accepted that expectations had risen following his impressive performances last season and at the World Cup. He dismissed suggestions that the criticism of his recent form had been unfair.
"It's clear to me that when you perform the way I did last season and at the World Cup, people judge you on that and expect you to score in practically every game. I understand that," Undav said.
Despite being aware of the scrutiny, he remained confident that his goals would return.
"But I've stayed calm. Of course, you see everything and hear everything, but I knew I'd score again eventually."
Undav added that he would happily sacrifice personal milestones if Stuttgart continued to win and remained on course to qualify for next season's Champions League.
"As long as we're winning, I could go without scoring and we'd still be playing Champions League football next season, and I'd take that. It doesn't bother me," he said.
"Getting my teammates involved and winning games is more enjoyable."
The 30-year-old also acknowledged that Stuttgart would not always be able to produce their trademark attacking football during a demanding run of fixtures.
"Of course we want to play beautiful Hoeneß football. That's clear, because that's how we've dominated a lot of teams," he said.
Stuttgart will now turn their attention to the Bundesliga, where they face Hamburger SV at the Volksparkstadion on Saturday.