Despite losing the first leg 2-1 in the Netherlands, goals from Archie Brown, Jhon Duran, Fred, Youssef En-Nesyri, and Talisca helped the Turkish side reach the playoff round of the competition. 

Feyenoord took the lead in the 41st minute through defender Tsuyoshi Watanabe, but Fenerbahce managed to take the lead before half-time after quickfire goals from Brown and Duran.

Fred and En-Nesyri helped Mourinho's side gain further control of the tie, but Watanabe popped up with another goal for the visitor to give Feyenoord hope of an equaliser.

However, Talisca scored a fifth deep into stoppage time as Fenerbahce secured a 6-4 aggregate win in style in Istanbul.

Mourinho praised the impact of the club's fans, particularly after they went a goal down, stating his side would have probably lost this match last season.

"Compared to last season, the decisive factor today was our fans," said Mourinho.

"When we were down 1-0, the scoreline was 3-1. If it had been last season, this would have been completely different. My players' situation would have been different too.

"When the scoreline dropped to 3-1, there was a positive feeling on the pitch. That was the difference compared to last season. The match was clear at every moment. The first goal we conceded was a farce. Then there was a crucial save from Irfan [Egribayat], right back. It could have made it 2-2, and he made a fantastic save.

"Our strength was also decisive. We're trying to adapt our players to what we have and what we don't. Of course, we don't have the same level of players as Feyenoord. The strikers are very aggressive, the midfielders worked hard, and the defence was very solid.

"Looking at today, we needed to be more solid on the second goal. We needed to keep the second goal. But it's the beginning of the season, and the team is very tired. Nelson was on vacation until a week ago. The midfielders have experienced a lot of difficulties. But I think we deserved more than the defeat in Rotterdam.

"Overall, I think the better side advanced."

Fenerbahce will face Benfica for a spot in the league phase of the competition after the Portuguese side defeated Nice 2-0 in the second leg, and 4-0 on aggregate.

Fred Aursnes scored the opener after 19 minutes before assisting Norwegian compatriot Andreas Schjelderup eight minutes later to give Benfica an unassailable lead in the tie.

Nice did not manage to register a single shot on target from their nine attempts, as Benfica outscored their Ligue 1 opponents 1.48 to 0.56 on expected goals (xG).