Morten Frendrup and Fabio Miretti struck for Genoa in Vieira's first game in charge, but Cagliari earned the point through two penalties converted by Razvan Marin and Roberto Piccoli.
“I am very satisfied and think the players put in an interesting performance,” Vieira told DAZN afterwards.
“It is disappointing because I think we deserved the victory, especially in the second half. The most important thing was to give the squad confidence, as they do have the quality to do well.
“We conceded two penalties and created numerous chances that we could’ve taken better. There is a lot that we need to work on.”
He continued: “It is honestly difficult to accept the second penalty, in particular. With all due respect to the referee, I think he got it wrong on the second penalty, but the first was irritating too. I do not agree with the explanation given by the referee and we cannot ask players to jump with their arms down.
“In any case, we have to set this aside and focus on the things we can control.”
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