Sala had been on his way from the French club to Wales on Monday night where he was due to start a new period in his career with Premier League Cardiff City.
Police said on Thursday that the chances of finding the 28-year-old Argentine alive were “extremely remote” as they announced they were ending their search.
“I had a particular relationship with him because from the moment of my arrival we talked a lot. I spoke with him…..” said veteran coach Halilhodzic who started to weep before composing himself enough to continue.
His voice still trembled as he added: “For me, it is perhaps the most difficult moment of my sporting life. I have known others but in terms of sport, this has left me completely shocked.”
Sala had been at Nantes since 2015 and had scored 12 league goals this season before signing a three-and-a-half-year deal with relegation-threatened Cardiff in a reported 17 million euro ($19.3 million) deal.
At Nantes’ training centre at La Chapelle-sur-Erdre in western France, the squad and staff met with fans who had gathered to pay their respects.
“Keep hoping,” said one poster which contained a picture of Sala and was pinned to the fence of the training centre.
Flowers and candles were also laid out as fans, numbed by Sala’s disappearance, held an emotional vigil for their former player.
“We know that he is lost, but there remains a small corner of hope that still exists,” 29-year-old Maxime Perrouin told AFP.
– ‘No minute’s silence – we still have hope’
After the Nantes squad had finished their training session for the day, players and staff were applauded by the fans who numbered more than 300.
“We ask you to stand united with us,” captain Valentin Rongier told them.
“We ask you to respect the family who absolutely refuse to talk about mourning and ask us to keep believing.
“It is for this reason that we are not going to have a minute’s silence or a minute’s applause because we still have hope.”
Perrouin, who was at the centre with his pet Huskie dog dressed in a Nantes shirt, said fans needed to pay their respects to Sala and support the team who are currenty just six points above the relegation zone in Ligue 1.
“The players really need us. I think it’s going to make them happy to see all the people gathered there for them and I think they’ll use it as a force to excel themselves on the field,” said Perrouin.
“I have tears in my eyes as I am talking to you, looking at his photo — it’s like we have lost somebody from our family.”
Another fan Andree Guittet, 69, who has supported the Canaries for 35 years, said she originally refused to believed the news of Sala’s disapperance.
“Someone phoned me — I thought it was ‘fake news’, it wasn’t possible.
“You couldn’t say he was a player like Neymar or Mbappe, but he was a battler, he was a warrior.”