Roma president James Pallotta branded the referee "disgusting" after his side were dumped out of the Champions League at the play-off stage by Porto.

Returning to the Stadio Olimpico with a 1-1 draw from the first leg, Roma were confident of progression to the competition proper but saw their hopes go up in smoke.

Already trailing 1-0, straight red cards for Daniele De Rossi and Emerson reduced Roma to nine men, with Porto taking full advantage by adding two more goals for a 4-1 aggregate success.

Head coach Luciano Spalletti rued his side's lack of discipline after the damaging defeat, but Pallotta preferred to focus his ire on match official Szymon Marciniak of Poland.

"He was disgusting," Pallotta said, in quotes reported by La Gazzetta dello Sport. "He ruined the match.

"You tell me, how can you be expected to play with 10 or nine [players], what else can you expect?

"No, there won't be any repercussions, but I'll say again, I'm extremely disappointed by the referee."

As a result of their loss, Roma drop into the Europa League group stages.