Nagelsmann, who agreed last summer to stay one more season at Hoffenheim before taking charge in Leipzig this year, looked like he was about to oversee a coup against his future side, but Leipzig captain Willi Orban equalized in the 89th minute to move his side within a point of third-placed Borussia Moenchengladbach.
Hoffenheim forward Andrej Kramaric scored in the 22nd on the rebound after Joelinton's initial effort was saved by Peter Gulacsi. Gulacsi made a brilliant reflex save to deny Adam Szalai what would have been Hoffenheim's second goal late on, before Orban made the home side's pressure finally count.
Leipzig, which was without Germany striker Timo Werner due to illness, consolidated fourth place, the last to qualify for Europe's premier competition, with Wolfsburg four points behind in fifth after round 23 from 34.
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