There was no official news about the fee Mönchengladbach paid for Vestergaard, but it was rumoured to be in the vicinity of 14 million euros. The Dane's old club said it was sad to see him go.
"Of course we would have loved to keep Jannik, and we tried to stress to him in our dicusssions how much he meant to us," Bremen sports director Frank Baumann said in a statement."But Jannik has sporting goals that we can't offer him in the near future, so we also said that we would listen if an offer was made that was sensible for everyone concerned.
Since arriving in Bremen in January 2015, the nearly two-meter-tall central defender played in 48 Bundesliga matches, scoring three goals. Vestergaard was instrumental in helping Bremen avoid relegation to division two last season.
Verstergaard's new deal with Gladbach runs for five years.