Donyell Malen scored a brace as Borussia Dortmund beat Cologne 4-0 on Saturday in a match delayed for eight minutes after protesting fans threw chocolate coins in gold foil onto the pitch.

Malen curled in a Julian Brandt cross to give Dortmund the lead after 12 minutes, immediately before supporters of both sides began their planned protest action.

Fans objected to the German FA's decision to allow greater foreign investment in the game, with players from both sides working alongside stadium attendants to remove the coins from the pitch.

The sides went into half-time after eight added minutes, Dortmund in control with a 1-0 lead.

Returned to the starting XI after a successful stint off the bench last week after rejoining the club on loan from Manchester United, Jadon Sancho won Dortmund a penalty early in the second-half, going down after contact from Rasmus Carstensen.

Niclas Fuellkrug converted to double Dortmund's lead and Malen added another shortly after, running onto a superb pass from Chelsea loanee Ian Maatsen to score his second.

Teenage striker Youssoufa Moukoko added a fourth in injury time to seal a second-straight victory for the visitors.

Also on Saturday, Bochum's home match with Stuttgart was delayed by 40 minutes after visiting fans refused to move flags blocking fire exits.

Referee Bastian Dankert delayed the restart after half-time due to the flags, with scores locked at 0-0.

Despite stadium announcements and a plea from Stuttgart manager Sebastian Hoeness to move the flags, the fans refused to comply as referees and officials from both clubs argued on the pitch.

Elsewhere, 10-man Freiburg downed Hoffenheim 3-2 at home to close in on the European placings.

Freiburg raced to a two-goal lead thanks to strikes from Lucas Hoeler and Vincenzo Grifo.

Hoffenheim pegged them back however through goals from Wout Weghorst and Max Beier to level the scores.

The home side were reduced to ten men when Manuel Gulde picked up a second yellow, but the setback galvanised Freiburg, who scored the winner shortly after through Roland Sallai.

Eintracht Frankfurt also surrendered a two-goal lead but were unable to find a winner, drawing 2-2 away at Darmstadt.

Darmstadt's Christoph Klarer scored in the fifth-minute of injury time to earn the last-placed home side a valuable point against their local rivals.

Wolfsburg's recent struggles continued, with Niko Kovac's men held 1-1 at promoted Heidenheim.