These are the same problems that Buckingham was wrestling with in recent weeks, but now his successor will be expected to find answers as quickly as possible.
But what are the situations that United’s new head coach will have to resolve?
READ ALSO: What next for Des Buckingham after surprise U’s sacking?
Battles at both ends of the pitch
The U’s have been struggling for a number of weeks now, with performances really starting to drop off with the 2-1 defeat at home to Swansea City at the beginning of November.
That was United’s first home loss of the season, and including the Swans match, over the course of the last eight games, there’s been a noticeable struggle at both ends of the pitch.
The U’s have scored just six goals, and only managed more than one in a game in the 6-2 loss at home to Middlesbrough.
Meanwhile, 18 goals have been conceded at the other end.
Losing Ben Nelson to a significant quad injury has no doubt hurt United, but the defensive solidity shown earlier in the campaign, in the goalless draw at home to Burnley for example, has vanished.
The U’s now look porous and the defence more exposed. Being hard to beat was the platform for early success in the season, and United must find a way to get back to that.
In attack, the creativity and sharp interplay seen at the beginning of the campaign has almost dried up.
There seems a lacking of belief and confidence, although in Buckingham’s final match, the weekend’s 3-1 defeat at home to Sheffield Wednesday, the U’s were much more creative, particularly in the first half.
Goals win games, and if United are to stay up, finding three points with increased regularity as opposed to draws is likely to be required.
Getting players back to fitness
Injuries have hurt the U’s season, and certainly hindered Buckingham’s options and team selection.
Much will be expected of club record signing Siriki Dembele, with his return from an ankle injury, alongside midfielder Louie Sibley, expected this month.
Wide duo Matt Phillips and Przemyslaw Placheta have returned in recent weeks, but are yet to get going.
They too need to get fully firing and live up to the expectations with which they arrived in the summer.
January transfer window
There will of course be more than an eye on next month’s transfer window.
If United are to survive in Sky Bet Championship this season, then the window will be key.
A centre back replacement for Nelson, a box-to-box midfield all-rounder, fresh wide options and perhaps an alternative centre forward should all be on the U’s shopping list.