Zdenek Zeman blamed “a lack of concentration” and the referee for Roma fumbling a 2-0 lead to lose against Udinese.
The Giallorossi have for the second time this season thrown away a 2-0 advantage for a 3-2 home defeat, having done the same with Bologna.
“After seeing the replays, I think it was not a foul for the penalty,” he told Sky Sport Italia.
“It has been a bad weekend for referees. People say they don’t decide tournaments, but I think on the whole they really can. Tonight Pablo Armero spat at Tachtsidis with the fourth official a few yards away, yet did nothing... For me, these things are decisive.
“We started very well, creating another three great scoring opportunities along with the two goals in the opening half-hour. After conceding with a push on Osvaldo that wasn’t spotted, we got irritable.
“Udinese play very well on the counter-attack and we were unable to stop them, so we conceded another two goals with our horizontal passes intercepted.
“If you don’t attack the ball straight away then you have problems. We ran backwards and it is difficult to defend like that. When we play our football and defend together, it is difficult to score against us.”
Roma are now seven points adrift of Inter in third place and their hopes of Champions League qualification are already fading.
“If I look at the first half-hour then I am not worried, as we are able to play good football and build something special. For now what we lack is concentration over 90 minutes. The things that seem simple ought to be treated with a greater sense of responsibility.
“Dodo has quality and is currently not 100 per cent fit. He is an important player who needs to settle tactically into the squad. Erik Lamela scored two goals and missed another two easier chances. He is trying to find the net, which for a striker is the most important thing.”