The 22-year-old looks set to snub a move to the Premier League where he has been heavily linked with Fulham, Everton, Aston Villa and Tottenham.
“Hamburg’s interest is very serious,” Groningen director Hand Nijland told Aftonbladet.
“I can confirm that we have had a personal meeting in Germany. Hamburg’s interest is very serious.
“I am expecting a call from Hamburg any moment. Hopefully we can have a meeting in Groningen (Wednesday).
“We have discussed the clubs with Marcus and his agent Soren Lerby and have been advised that Hamburg is Marcus’ first choice.”
“We will see,” said Berg’s agent, Soren Lerby. “First the clubs need to agree. Of course this is an interesting possibility. But right now I can’t say more than that.”
