Union Berlin's Leopold Querfeld converted a late penalty to snatch a 1-1 Bundesliga hone draw on Friday spoiling Albert Riera's as Eintracht Frankfurt coach.
Appointed Monday, Riera was on track for a dream start in the dugout when Nathaniel Brown broke Union's stubborn resistance with six minutes remaining.
Three minutes later, Frankfurt's Oscar Hojlund yanked Union captain Rani Khedira down in the box, allowing Querfeld to convert from the spot, denying Frankfurt a first win of 2026.
Despite the late disappointment, Frankfurt will be buoyed by an improved defensive performance.
Frankfurt have now conceded 46 goals, more than any other Bundesliga side. They had shipped at least three in six of their past seven matches before arriving in the German capital.
The point takes Frankfurt past Freiburg into seventh, while Union sit two spots and three points back.
Speaking before the match, former Liverpool and Manchester City midfielder Riera said he wanted to help instil "a new playing style and a new identity" to a defensively brittle team.
The best chance in the opening half was a long-range effort from Union's Aljoscha Kemlein which forced a one-handed save from an airborne Frankfurt goalie Kaua Santos.
The visitors broke through when Brown lashed in from close range.
Union struck back almost immediately, with Querfeld slipping his spot kick under Santos after Hojlund saw a second yellow for a foul on Khedira.
On Saturday, Borussia Dortmund can move three points behind league leaders Bayern Munich with a win at struggling Wolfsburg.
Bayern host third-placed Hoffenheim on Sunday.