Newcastle piles pressure on United
The result condemned United to back-to-back home Premier League defeats for the first time 2002.
It meant United have lost five times already this season and that they have collected just two points from their last four games.
Little wonder the reaction at the end was one of anger from the home supporters, who watched virtually the same group of players they booed off today clinch a 20th title by 11 points less than seven months ago.
For Moyes, it is absolutely the stuff of nightmares.
The Scot has been dignified in rolling the heavy blows that have already been inflicted upon him during his short tenure and he retains the unquestioned support of the club's owners.
Yet it seems patience elsewhere has started to wear thin.
When Patrice Evra's clearing header bounced back off Moussa Sissoko, allowing the Newcastle man a free run into the area, before cutting back a perfect cross to invite Cabaye's first-time finish, albeit via slight deflection off Nemanja Vidic, the discontent rippled round all but a small corner of the stadium.
Amid their glee, the Magpies fans delivered two of the cruellest jibes. They suggested Moyes would be sacked in the morning and that United would be accompanying Sunderland into the Championship at the end of the season. And it is true that United are nearer the drop zone than they are the top spot they occupied for so long.
As the whistle blew on yet another goalless first-half for United, it was hard not to feel a little bit of sympathy for a set of players who appeared paralysed by fear.
Seven changes from the midweek defeat by Everton, including the return of Robin van Persie following a four-match absence with a groin strain, should have had a positive impact.
But the additional mobility compared to Wednesday was lost amid the tentativeness of a team who looked scared to lose in front of a crowd on the brink of a very negative reaction.
Too often invention was spurned in favour of safety, which in turn reinforced the defences of a solid Newcastle outfit, who never looked in danger of coughing up the type of goals they did at Swansea on their last outing.
Player-of-the-month Tim Krul pulled off a decent save from Phil Jones in the early stages but had little else to do in the first-half.
Fabricio Coloccini made an excellent clearing header to prevent Vidic getting to Adnan Januzaj's cross, whilst the young Belgian was robbed in the box brilliantly by Yoan Gouffran.
And other than a blatant dive by Javier Hernandez, that was that for the hosts.
Newcastle did not do that much better.
But with Cheick Tiote controlling midfield and Loic Remy remaining on the move, United's defence did not look as settled as Newcastle's.
And when Evra was caught out of position, allowing Remy to slide a brilliant pass through for Mathieu Debuchy, whose thunderous first-time shot was turned away one-handed by David de Gea.
De Gea moments later repelled a close-range Debuchy header to at least ensure United reached the break level.
Moyes appeared to have used the interval wisely, judging by the sense of purpose his side had at the restart.
Krul saved from Hernandez and Januzaj before Evra met a Nani corner with purpose and sent a header bulleting against the post.
Vurnon Anita had no chance to react as the rebound struck him on the hand from barely six inches.
As the ball was flashing straight across goal and the diversion helped take it away to safety, a penalty surely should have been awarded. Instead referee Andre Marriner waved play on, just as he did when Tiote cut down Evra close to the Newcastle goal-line moments later.
Incidents like these tend to be followed by a hammer blow. And Cabaye duly provided it with his 10-yard finish from Sissoko's cross - via Vidic.
The introductions of Wilfried Zaha for his Premier League debut and Anderson looked like the reactions of a desperate man, just as the noise appeared to be when Van Persie turned home what he thought was an equaliser. A brilliant call by assistant referee Sian Massey ruled otherwise.
United continued to push forward but to little effect and when Marriner called time on another sorry day, there were thousands of empty seats.
Those who remained let their feelings be known in a different way.