BERLIN, Oct 16 (Reuters) - Union Berlin's Janik Haberer scored twice in 13 minutes as the Bundesliga leaders cruised past Borussia Dortmund 2-0 on Sunday to open up a five-point gap at the top of the league table.

Haberer first pounced when Dortmund keeper Gregor Kobel miskicked the ball, to tap in from close range in the eighth minute and then drilled in another with a powerful shot from the edge the box in the 21st.

Dortmund's backline was leaking like a sieve in the first half and the visitors were lucky to go into the break with just a two-goal deficit as Union's Sheraldo Becker wreaked havoc down the wing.

They improved after the break and Kobel redeemed himself for his first-half error with a full-stretch save to stop a Timo Baumgartl header but they completely lacked ideas in attack to threaten the hosts.

The win put leaders Union, who have the league's best defence, on 23 points, backlink programı five ahead of Freiburg who have 18 and face Bayern Munich, backlink programı on 16, later on Sunday.

Dortmund's fourth league loss of the season saw them drop to eighth on 16.

(Reporting by Karolos Grohmann Editing by Toby Davis)