Sevilla said that Vaclik “suffered a sprain of the internal lateral ligament in his left knee” on Monday night and that it was not yet clear how long he would be out.
Because Sevilla had used all their substitutes, Argentine winger Lucas Ocampos, who had earlier scored the only goal, took over in goal.
In the 11th minute of added time, he preserved the victory when he saved a close-range shot by opposing goalkeeper Marko Dmitrovic, who had come up for a corner.
The 1-0 victory cemented Sevilla’s grip on fourth place.
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