Sevilla coach Julen Lopetegui said he feared Lucas Ocampos had suffered a serious injury in Saturday's 3-0 La Liga win over Getafe after a foul by Djene Dakonam, but regretted his furious reaction to the incident.
Togo centre-back Djene was shown a straight red card for treading on Ocampos' ankle and Lopetegui clashed with Getafe coach Jose Bordalas, leading to both managers being sent off.
"I have to apologise publicly for my outburst. I had just seen my player in a terrible way but I could have acted differently," Lopetegui told reporters.
"The most important thing is that Ocampos gets well soon and it's not serious but the Sevilla coach should behave better than that."
Lopetegui did not hide his concern for Ocampos, who was seen screaming in agony as he was carried off the pitch on a stretcher.
"We're very worried for Ocampos. We think it's a very big injury," Lopetegui said. "He said he was seriously injured but we're crossing our fingers and hoping it isn't. No-one wants to see a player in a predicament like that."
Getafe's Bordalas said Djene was "distraught" after seeing how badly he had injured Ocampos.
Bordalas also felt his own sending off for his row with Lopetegui was not deserved, and was highly critical of his opposite number.
"I was sent off because of a rival coach and I'm very sad because I always want to help out my colleagues, even though we are fighting for different objectives. I feel awful, I feel unfairly treated and unfairly sent off," he said.
"I feel terrible about the injury. The thing a professional wants to see least of all is injuries. But unfortunately when I went over to see how the boy was the Sevilla coach went after me as if he was blaming me.
"I felt assaulted, and I think he showed me a lack of respect."