Rossi helps Fiorentina beat Pacos
The 26-year-old forward from New Jersey scored the hosts' final goal in the 76th minute on a left-footed shot from 12 yards, his fourth goal in five matches this season. Gonzalo Rodriguez scored the opening goal in the 30th minute when he headed in Rossi's corner kick.
Rossi tore the anterior cruciate ligament in his right knee playing for Villarreal against Real Madrid in October 2011 and had three operations before returning with Fiorentina on May 19.
Swansea won 3-0 at Valencia on goals by Wilfried Bony, Michu and Jonathan de Guzman. Adil Rami was ejected in the 10th minute for fouling Bony.
Valencia fans emptied the stand in the bottom tier behind one of the goals for 10 minutes at the start of the second half protesting a poor start that included three losses in the team's first four La Liga matches.
Bulgaria's Ludogorets Razgrad scored twice in the second half to win 2-0 at PSV Eindoven.