Fofana arrived at the Sánchez-Pizjuán on loan from AC Milan without an option to buy, running until June 2027, after Lyon's attempt to re-sign the midfielder collapsed late on deadline day when the French football finance watchdog blocked the move over the club's failure to first sell Malick Fofana.
Sevilla moved swiftly to take advantage of the opening, completing the deal in the closing minutes of the window.
Del Nido Carrasco explained just how tight the timeline had been.
"The coach had asked us that, to complete the squad, he wanted a six, a holding midfielder. To satisfy that request, on the last day of the window we moved heaven and earth until the Olympique Lyonnais deal for Fofana fell through and he became available on the market. It was around 20:12 or 20:13, and by 23:57 we had submitted the paperwork on the league's platform — the boss said it himself, all we were missing was a call to the Pope to convince Youssouf to become a Sevilla player," the president said.
Fofana admitted the day had been a whirlwind for him too, speaking to the club's official media after his arrival.
"For me it was a bit of a crazy day. It started a little out of control, but in the end I'm very happy to be here. I think it was the best option for me.
"I thought about the club's history, about what's happening right now, and I wanted to be part of Sevilla's rebirth, to help return it to where it's been in recent years," he said.
Asked whether any budget remained for the January window, Del Nido Carrasco was cautious.
"In terms of our spending limit, we've used up practically all the capacity we generated from departures. Every squad, even the best team's, can always be improved, but we're all happy with the squad and convinced that under the coach's leadership it will be competitive. We'll see in winter whether we've fallen short and need to generate more room to make a signing," he said.