Goals from Ashley Young and Javier Hernandez were enough to seal a 2-0 win and give Ajax a mountain to climb next week at Old Trafford. Barring a huge shock, United should now progress to the Europa League last 16.
Ferdinand, captain for the night in the absence of Patrice Evra, was all smiles at the final whistle, although he acknowledged the Reds' performance was far from vintage.
"It was a good result," he said. "I think before the game we would have taken 2-0 had you offered it. To come away with a victory and a clean sheet was pleasing.
"It wasn't one of our best performances, but sometimes you get that. In this type of tournament, in the knockout stages, the result is the most important thing."
The 33-year-old reserved his biggest praise for those returning from knocks. Jones and Nani hadn't featured for four matches and both completed 90 minutes, while Cleverley laced up his boots for the first time since late September. He completed an hour and looked sharp throughout.
"It's important to recognise we had a few players who have been out recently and were able to get a few minutes under their belts. That was good.
"In Tom's case, he's an all-round player and the sort of guy who's going to be beneficial to the team. He's got a lot of energy and he's a good passer of the ball. It's good to see him back."
The news from Amsterdam wasn't all good, though. In setting up United's second goal, Antonio