Kevin Constant had a banana thrown in his direction in Milan's Serie A fixture at Atalanta - the second such incident in a matter of weeks after Barcelona's Dani Alves was targeted in a similar fashion at Villarreal.
In Russia, Zenit's game with Dinamo Moscow had to be abandoned in the closing stages as home fans invaded the pitch at the Stadion Petrovskij.
Andre Villas-Boas' men came into the clash knowing victory would guarantee they entered the final round of Russian Premier League fixtures as leaders.
One fan appeared to direct a punch at Dinamo's Vladimir Granat, and Blatter took to Twitter to express his disappointment at both incidents.
"Racism, and games stopped/abandoned due to acts of hooliganism. Each Federation needs to act. Sanctions are available & HAVE to be applied," he said.
