In front of a sparse United crowd amid a fan protest against the Glazer ownership, Chelsea quickly settled into a good rhythm.
Kai Havertz was guilty of squandering the visitors’ most significant openings in the first half, whipping a shot against the side netting after a breakaway before slapping a one-on-one shot against David De Gea’s shoulder.
The goalkeeper was then able to deny a free header, straight at him, as Chelsea produced everything but a finish.
Reece James and Mason Mount were enjoying the freedom of Manchester down the right and the midfielder attempted to prise open the deadlock with a whipped cross that beat De Gea, and Timo Werner, shortly after the break. Beforehand, Havertz had again wasted a good counter with a sloppy pass.
It was no surprise when Marcos Alonso popped up, unmarked, to fire Chelsea ahead on the hour mark after another move down the right.
But even the most optimistic of home fans would not have expected Cristiano Ronaldo to appear moments later and slam home a leveller, after good work from Nemanja Matic.
That goal did little to lift United in the grand run of the game and James hit the post with a left-footed strike from outside the box after a nice tee-up by Mount. But the Red Devils held on for a point.