BERLIN (AP) — Union Berlin drew with Bayer Leverkusen 0-0 to stay third in the Bundesliga on Saturday, when Freiburg and Leipzig won their games as the battle for Champions League qualification intensified.

Japan midfielder Ritsu Doan scored for Freiburg to win in Cologne 1-0 and stay fourth, just behind Union on goal difference, while Christopher Nkunku’s first-half strike was enough for Leipzig to win at Hoffenheim 1-0 and move to two points behind both Union and Freiburg.

The top four qualify for Europe’s premier competition. Four rounds remain after this weekend.

Both Union and Leverkusen stretched their unbeaten runs. Union was unbeaten in 21 games at home – a club record – while Leverkusen extended its unbeaten run to 14 games across all competitions.

Xabi Alonso’s team hasn’t lost a game since Feb. 19.

A scoreless draw was perhaps the predictable outcome from a meeting of teams with the best defenses in the league.

Union made the better start and pushed for the opener – cautiously. Urs Fischer had clearly warned his players of Leverkusen’s threat on counterattacks.

Leverkusen star Florian Wirtz showed brief glimpses of what he was capable of but otherwise the home team maintained control.

Stuttgart boosted its hopes of survival with a 2-1 win over Borussia Mönchengladbach. Tanguy Coulibaly scored a late penalty for Stuttgart to leave the relegation zone on goal difference ahead of Bochum, which drew with league leader Borussia Dortmund 1-1 on Friday.

Eintracht Frankfurt drew with Augsburg 1-1.

Schalke hosted Werder Bremen late.