(Reuters) - Nottingham Forest manager Nuno Espirito Santo said it is difficult to digest refereeing mistakes after his side was denied several penalty shouts in their 2-0 Premier League defeat against fellow relegation-threatened club Everton on Sunday.

The Forest camp was angry at being denied three penalty claims, all against Ashley Young after the Everton full back knocked the foot of Giovanni Reyna, followed by a handball claim and a challenge on Callum Hudson-Odoi in the box.