Mourinho was sent off after protesting Real Betis’ third goal, which seemed to go off the attacker’s arm
Mourinho furiously approached referee Jorge Figueroa after Betis’ third goal was allowed to stand, despite an apparent handball from Alex Moreno.
Roma’s Lorenzo Pellegrini was also sent off following the incident, which put Betis 3-2 ahead in the 57th minute, and Mourinho was sent to the stands for his protests.
Defender Gianluca Mancini was then shown a straight red card in the 65th minute before Rick Karsdorp was also dismissed with 10 minutes to go. Betis added two late goals to condemn Roma to a 5-2 defeat.
Roma begin their Serie A campaign away to Fiorentina on 22 August.
Mourinho had been linked with signing Arsenal midfielder Granit Xhaka for his new club, but the Gunners man now appears set to stay and pen a new deal instead.