The visitors issued a statement of intent inside the opening minute courtesy of talisman Hugo Ekitiké, with his effort impressively saved by Lasse Rieß, who was making his senior debut.
Soon after, the hosts suffered a significant blow as Dominik Kohr sustained a serious-looking injury to his left knee, with Stefan Bell coming on to replace him.
Mainz then began to settle into the contest, until out of the blue, Rasmus Kristensen benefited from a fortunate ricochet that allowed him to find Ekitiké, who returned the pass for the Dane to finish past the onrushing Rieß.
The hosts suffered more injury woe midway through the first period as Danny da Costa was withdrawn, with Silvan Widmer coming on to don the captain’s armband, before there was another brief pause due to paper balls being chucked at corner taker Nadiem Amiri by the Frankfurt fans.
Mainz thought they had equalised in first-half stoppage time as Anthony Caci’s lovely pinpoint cross was headed home with aplomb by Lee Jae-sung – who had missed a presentable chance a couple of minutes earlier – only for the offside flag to be raised.
However, Mainz refused to allow their heads to drop, and they came out after the break looking the more threatening of the two sides, drawing level on 57 minutes.
Widmer’s throw-in was flicked on to the back post, where Kristensen, unaware of Jonathan Burkardt’s presence, booted the ball against him for it to agonisingly loop out of the reach of Kevin Trapp.
Bo Henriksen’s men began to sense that a win was possible, a sentiment shared by the home crowd, although the threat of Ekitiké remained as the Frenchman miscued a lob on 69 minutes.
Ultimately, however, in a game of few big chances, it was Ekitiké again who could have netted the winner, only for his dink to just go wide of Rieß’s right-hand post, while Burkardt also had a late opportunity, skewing off-target.
After missing out on their first league double over Frankfurt in five years, Mainz are winless in seven Bundesliga games, but sit just two points adrift of the European places with just two games of the season left to play, while their opponents here need one more win this term to secure UCL football in 2025/26.
Flashscore Man of the Match: Robin Koch (Eintracht Frankfurt)