Life in the Bundesliga began in silence for Union Berlin with a 15-minute protest by the club's fans against opponents Leipzig.

A minute after Union fans finally unleashed their support on Sunday, it was the visiting supporters making all the noise after Leipzig scored the opening goal in a 4-0 rout of the first team from the former East Berlin to play in Germany's top flight.

The home fans stayed quiet for the opening 15 minutes, answering a call from Union ultra group Wuhlesyndikat, which had urged supporters to protest what they called "a constructed club that has absolutely nothing to do with our idea of football."

Red Bull-backed Leipzig has been unpopular among rival fans since its formation in 2009. The energy drinks manufacturer founded the club and helped finance its steady progress through the lower leagues to the Bundesliga.

The team is used to protests — Dynamo Dresden's fans threw a severed bull's head onto the field during a cup game in 2016 — and Union fans' silence was just the latest for the players.

"I wasn't paying attention. Our fans created atmosphere, so from that point of view ... (it) was all the same to me," goal-scorer Marcel Halstenberg told The Associated Press. "We concentrate on ourselves."

Halstenberg's opening goal was followed in the first half by goals from Marcel Sabitzer and Timo Werner. Substitute Christopher Nkunku marked his debut with a goal after the break, underlining the gulf in quality between teams that finished third in their respective divisions last season, and giving Julian Nagelsmann a winning start in his first league game in charge of Leipzig.

Union's previous biggest achievement was winning the East German Cup in 1968, but the Köpenick-based side secured promotion on away goals after two draws with Stuttgart in the playoff in May.

The club made 12 new signings over the summer to help its bid for survival, but rarely looked like troubling a Leipzig team boosted by an investment of more than 50 million euros ($56 million) in signings.

"At least we've arrived (in the Bundesliga) but we've been brought back to earth," Union coach Urs Fischer said. "Leipzig were clearly better and fully deserve the win."

Wuhlesyndikat's protest caused divisions among Union's fans, but club president Dirk Zingler said it would behave in the Bundesliga like it had in the second division, where it had also opposed Leipzig.

"It's painful for us that it's in the first game. Perhaps that's why it's also particularly strong, to really do it in the first 15 minutes. The ultras have the club on their side," Zingler told local broadcaster Radio Eins.

Before kickoff, as the Union anthem was blasted out around the stadium, fans held up posters of deceased supporters, so they could be there for the club's Bundesliga debut, too.

Once referee Markus Schmidt got the game underway, only the Leipzig supporters could be heard, though the Union fans couldn't contain themselves when Robert Andrich went close.

The fans ended their boycott with a burst of clapping and chanting, and Leipzig's answer was prompt as the team threatened to run riot. Besides the goals, Lukas Klostermann had a goal ruled out through VAR, and Yussuf Poulsen struck the crossbar.

Nkunku, a summer signing from Paris Saint-Germain, came on for Werner in the 65th and scored two minutes later.

Union's fans never stopped, however, making up for their earlier silence. They sang long after Schmidt blew the final whistle — "Our love, our team, our pride, our club."

Eintracht Frankfurt beat Hoffenheim 1-0 at home in the early game.