Champions League hopefuls Frankfurt crashed to a 4-3 defeat at relegated Schalke on Saturday with U.S. star Matthew Hoppe scoring the winner.
Hertha Berlin substitute Jessic Ngankam snatched a 74th-minute winner as his team came from a goal down to beat already-relegated Schalke 04.
The fan attacks on Schalke 04 continue to shake the German club after the Bundesliga side were relegated on Tuesday.
Schalke players were attacked by their own fans when returning from Bielefeld after being relegated from Bundesliga for the first time in 30 years.
Schalke 04 were relegated from the Bundesliga for the first time in 33 years on Tuesday after losing 1-0 to fellow strugglers Arminia Bielefeld.
Suat Serdar celebrated his 24th birthday by scoring his first Bundesliga goal of the season as Schalke ended a 12-game winless run to beat Ausburg.
Bundesliga basement club Schalke 04 drew 0-0 at home to Mainz 05 in their relegation derby on Friday in coach Dimitris Grammozis' debut.
Juventus have confirmed the signing of United States midfielder Weston McKennie on a permanent deal.
Schalke 04 hired the relatively unknown Dimitrios Grammozis as their fifth coach of a turbulent season on Tuesday.
Schalke's problems continued as they sacked their first-team staff to become the first Bundesliga club with five different coaches in a season.
Borussia Dortmund have criticised players, including Emre Can and Erling Haaland, who took part in celebrations with fans.
Borussia Dortmund crushed Schalke 04 4-0 in their Ruhr valley derby on Saturday, with two goals from Erling Haaland.
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