The Hoops produced their most listless display of the season in Europe's premier club competition to fall bottom of their group and the Nigerian defender has revealed that manager Neil Lennon was not at all happy with the way his side performed.
"The manager wasn't happy. After the way we played first half, you can never be happy," said Ambrose.
"He asked us to step things up. He was angry because he knows we can do better than we did in the first half. We knew Ajax would come on to us and we had a game plan to combat that and get forward.
"It didn't work and that was a major disappointment. We just couldn't keep the ball.
"That was the most difficult part of the first half for us. Our passing wasn't good enough. We needed to be better on the ball and we wanted to change that in the second half.
"So then to concede a goal soon after the restart was disappointing. It was a careless one to concede. They got through too easily."
He added: "We need to use the ball better and learn from this. We need to be brave on the ball. We know we can do that. Ajax are a good team and deserved to win. They were better than us, but we need to keep believing.
"This is not over, we believe this group is open and that we can get a result against AC Milan and still qualify.
"We need to accept what happened and look forward. There is a lot of hard work ahead."
For breaking stories and all the great banter like us on Facebook: facebook.com/tribalfootball