Vega was called up to Mexico's U-23s for training in preparation for the Olympic qualifiers next March and in a friendly against Cruz Azul last Sunday to end the camp, the 22-year-old picked up a right ankle sprain after a tackle from La Maquina's Uruguayan midfielder Ignacio Rivero.
Vucetich was left livid, with Chivas involved on Saturday against Necaxa in the play-in round to the Liga MX playoffs and Vega now out for between four-to-six weeks, according to the club.
"There's wasn't a medical report, they didn't carry out a test, they didn't give him the necessary attention," said Vucetich in an interview with TUDN. "It is unforgivable."
"Things should be done in the right way, looking out for, first of all, the interests of the clubs," he continued. "The players belong to the clubs and we support the national team with pleasure."
Chivas have made a formal complaint in a bid to suspend Rivero, who Vucetich and the club believe intentionally went out to hurt Vega. There is also a realistic possibility of Cruz Azul facing Chivas in the quarterfinals next week, depending on others results and Chivas overcoming Necaxa.
"It's based on an investigation by the directors," said Vucetich. "They spoke to players about what had happened, there was an internal situation in which Ignacio Rivero had previously tried to kick [Vega]."
Vucetich added that Chivas midfielder Fernando Beltran was also targeted in the same game and questioned the logic of the U-23s playing a friendly against a team still in the Liga MX playoffs.
Chivas' sporting director Ricardo Pelaez released a video statement on Monday indicating he believed the challenge by Rivero was "malicious" and that the club is looking for Rivero to be banned. The Mexican federation confirmed Chivas' complaint had been received on Tuesday and that it is investigating.
Cruz Azul has yet to make an official statement on the matter, although ESPN's Leon Lecanda reported that the club will back Rivero and believes that there wasn't anything untoward in the play.