Bartomeu, who served as Barcelona president from 2014 to 2020, spoke to ESPN Deportes ahead of Sunday's El Clásico — a match in which both Vinícius and Mbappé could face a Barcelona side that came close to signing them at earlier stages of their careers.
On Vinícius, who was playing for Flamengo in Brazil before his move to Real Madrid was announced in May 2017 for €45million, Bartomeu was specific about how far negotiations had progressed.
"Vinícius interested the club. We spoke with his family and with his agents, and there was indeed an initial agreement. Madrid possibly made a better offer and ended up signing him."
The Brazilian has since made 372 appearances for Real Madrid, scoring 127 goals and winning two Champions League titles.
The Mbappé situation, Bartomeu explained, was different in character. Monaco's valuation placed the deal beyond what Barcelona could commit to at that point.
"Monaco was asking for very high figures that Barça could not pay at that time. I remember speaking with Mbappé's father a couple of times, but Paris Saint-Germain put a lot of pressure on Monaco and I think Mbappé also preferred to go to PSG — a French team. We were negotiating with Ousmane Dembélé, who was the coaches' preferred player."
Bartomeu was also asked about the Negreira case — the ongoing judicial matter in which Barcelona are accused of making payments to José María Enríquez Negreira, the former vice-president of the Spanish refereeing committee, while Bartomeu was president.
"It has been suggested that Barça paid to buy matches or influence refereeing decisions — and this is not true. Barcelona paid for refereeing reports and match analysis services provided by Javier Enríquez, who is the son of Mr. Negreira."
He was unambiguous about what he expects the process to conclude.
"The matter is under judicial review. I expect — and I believe — that we will not reach trial, because there is no evidence proving that Barcelona paid a referee. All the Spanish referees have testified and said the same thing: 'I have never received a request. No one has ever asked me for anything.'"
He acknowledged that payments were made and that their scale may be open to scrutiny, while maintaining there was no corrupt intent behind them.
Barcelona need only a draw on Sunday to be confirmed as La Liga champions. Vinícius and Mbappé line up for the side that could have employed them both.