Feyenoord knocked AC Milan out at the San Siro after securing a 1-1 draw. A 1-0 win in the first leg in Rotterdam meant the end of the road for Milan and a first round-of-16 appearance for Feyenoord since 1993.
"It will dawn on me in the hotel," said Bosschaart after the game. "For now, it's very nice. When you see how happy everyone is... What a great night.
"This says everything about the group, They have character. I am most proud of that."
Bosschaart assumed the role of caretaker manager after Danish boss Brian Priske got sacked right before the first leg of the Champions League knock-out phase. Under Priske, Feyenoord beat the likes of Bayern Munich and Benfica and got a famous comeback draw away at Manchester City, but disappointed in the Dutch Eredivisie with Feyenoord and couldn't connect with the squad, according to Feyenoord technical director Dennis te Kloese.
Bosschaart has stayed unbeaten in his first three games in charge of Feyenoord, beating Milan 1-0 in Rotterdam before drawing 0-0 to NAC Breda and 1-1 at the San Siro.
"They are in a very difficult phase with a lot of criticism. They went through a coaching change. Then some unknown gets in front of the group who sometimes throws in some empty phrases," joked Bosschaart. "But we are very clear, honest and transparent. And they respond great to that."
Feyenoord conceded a very early goal in Milan, falling behind only 37 seconds into the match at the hands of former star man Santiago Gimenez. ‘When you conceded a goal that quickly, you are not sharp enough. The plan we wanted to execute also became different," Bosschaart said.
Feyenoord got a lucky break when AC Milan were reduced to ten men after Theo Hernandez got a second yellow card for diving.
‘But we did not give away many very big chances. Everyone will now say that that red card is why we won, but I thought we were already playing under it at times in the first half. After the red card, it went easier."