Jurgen Klopp's side had won eight on the bounce heading into the clash and were hot favourites to continue their dominant start to the Premier League season.
United were severely understrength, with Mohamed Salah the only key man missing for the visitors.
However, the Reds were lucky to leave the Theatre of Dreams with a point after a spirited and dogged display from Ole Gunnar Solskjaer's side.
Marcus Rashford gave the Red Devils the lead shortly before the half-time interval and it took Liverpool until the 85th-minute to draw level.
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Andy Robertson's cross somehow evaded every United defender, before reaching Adam Lallana for a simple tap-in.
It was the Englishman's first goal for the club in two-and-a-half years and one that means Liverpool are still six points clear of Manchester City at the top of table.
And a key goal in Liverpool's season is made even better when it's narrated by the best commentator in the game, Peter Drury.
The poetic genius was at it once again at Old Trafford, evoking more memories of those ITV Champions League nights with the tag team of Drury and Jim Beglin.
We need Drury back on English television on a regular basis!
Last season, we were treated to a small snippet of Drury's magical tones when he was selected to commentate on Ajax's memorable victory at Real Madrid in the Champions League.
As usual, he delivered a linguistic masterclass and you can watch the highlights of that game below.
You will definitely want the sound on.
Like music to the ears.
Whenever there's a big moment in a big game, you can always rely on Drury to elevate it to new levels.News Now - Sport News