Egypt striker Mohamed Zidan joined Borussia Dortmund as substitute during a last-gasp 1-1 draw at Hamburg on Saturday to increase their lead to eight points with five games left.
Egypt and Dortmund striker Zidan came off the bench in the 75th minute and helped the Bundesliga leaders to seal their away draw as Hamburg clinched a well-deserved point.
Dortmund needed an injury time goal from substitute Jakub Blaszczykowski to earn a 1-1 draw at 10-man Hamburger SV and remain on course for the Bundesliga title.
But the leader has won only one of its last four games and Bayer Leverkusen can move within five points if it beats struggling St Pauli on Sunday. There are five matches to play.
Hannover beat Mainz 2-0 to move back into third place past Bayern Munich, which had to settle for a 1-1 draw at Nuremberg.
Wolfsburg lost 1-0 at Schalke and 10-man Freiburg beat Hoffenheim 3-2.