Emil Forsberg drilled in a second-half winner as RB Leipzig were made to work hard for a 1-0 victory over in-form Union Berlin on Wednesday that kept them on the heels of leaders Bayern Munich.

Sweden international Forsberg, who had come on 10 minutes earlier, fired in after a one-two with Dani Olmo to break the deadlock in the 70th minute after a largely toothless first half from the hosts.

Leipzig keeper Peter Gulacsi came to their rescue in stoppage time, palming a powerful shot from Marius Buelter wide.

The win lifted Leipzig to 35 points, four behind Bayern, who edged past Augsburg 1-0 to stay top at the season's halfway mark.

Union suffered their first loss in seven league games and dropped to sixth on 28.