Sead Kolasinac's second-half strike was enough for Schalke to win 1-0 at Mainz and record just their second Bundesliga away victory of the season.
Kolasinac struck five minutes after the break on Sunday, playing a one-two with Guido Burgstaller when he was surrounded by a host of defenders before running on to shoot inside the right corner.
The goal settled the visitors while Mainz were forced to press forward in search of an equaliser.
Pablo De Blasis sent Jhon Cordoba through but Schalke goalkeeper Ralf Faehrmann gathered the ball.
Nabil Bentaleb should have wrapped it up late but failed to get the better of Jonas Lossl in a one-on-one with the goalkeeper.
Schalke moved into ninth while Mainz stayed 12th, among four teams just two points above the relegation zone.