Watched from the sidelines by imminent signing Samuel Eto'o, Sampdoria were given a sixth-minute lead by Eder only for Franco Vazquez to pull the Sicilians back into the match four minutes after the restart.
But the Genoa-based side should have been trailing by a goal when Michel Morganella beat 'keeper Emiliano Viviano with a rocket that smacked off the crossbar and bounced over the line and back out of goal.
Match referee Angelo Cervellera ruled the ball had not crossed the line, but even Mihajlovic broke his silence on talking about official decisions to speak out in defence of the visitors.
Speaking to Mediaset Premium, Mihajlovic said: "I have to be honest, it was clear. I don't usually talk about refereeing decisions but among the things we we need to adopt is Goal-Line Technology."
Fourth in the table on the same points as third-placed Lazio, Sampdoria are one of several teams engaged in a tight battle for the third and last Champions League qualifying spot.
They have conceded only two defeats all season, and club president Massimo Ferrero has lofty ambitions - in recent days he has signed four players, including Udinese striker Luis Muriel, and is on the verge of signing Eto'o from Everton.
Eto'o passed a medical on Friday and the Cameroonian should complete his transfer early this week having watched Sunday's game with Ferrero and then been paraded to fans by the flamboyant film-maker after the game.
Mihajlovic, however, has yet to decide how to deploy the strikers, signed to plug the gap left by the departure of Manolo Gabbiadini to Napoli several weeks ago.
"Muriel and Eto'o both like to play as stand-alone strikers but they can also play other roles, like playing wide in a 4-3-3," added the Serbian. "We'll see, Samuel used to play wide early on in his career.
"He should be ready to play. He's been training and played up until a few weeks ago. From Tuesday, we'll have a close look at him but we think he'll be ready."