Mourinho took just 15 days to find a new job after being sacked by Spurs, with the Special One appointed as Roma’s new head coach for the 2021/22 season.
Fonseca, who will make way for Mourinho, could still leave on a high – but his team will need something special to reach the Europa League final as they bid to overturn a 6-2 semi-final first-leg defeat to Manchester United.
The news of Mourinho’s impending arrival has lifted the club as they sit seventh in Serie A, and Fonseca believes the Portuguese will be a success in the Italian capital.
“For me, professionalism is something I believe is very important,” the outgoing Giallorossi boss said on Wednesday.
“I am OK, I am focused on things here just like I was the very first day I got here.
“I am motivated. I want to do the best I can for Roma for as long as I am still here.
“Mourinho is a great coach, everyone knows that, and I am sure he will do a great job here.”
Fonseca is realistic about the difficult task facing Roma on Thursday night, but has told his players to target a win first and build something from that spark of hope.
“Clearly it is not easy to beat Manchester United by four goals – but I have seen a lot of things happen in football,” he added.
“Nothing is impossible. I believe that anything can happen.
“I’m expecting a tough game. Going up against Manchester United is always very difficult.
“They have a good first-leg advantage but we want to win the game. We want to fight until the very end.”
Additional reporting by PA.