Substitute Javier Hernandez earned Manchester United a point after England striker Wayne Rooney was left out of the starting line-up at Anfield.
The Mexican levelled nine minutes from time after Steven Gerrard, making his first start since undergoing groin surgery in April, put Liverpool ahead with a 68th-minute free-kick.
Manchester United manager Sir Alex Ferguson revealed he dropped Rooney after he was left "devastated" by the that rules him out of England's Euro 2012 group games following his red card in Montenegro.
As well as Rooney, Ferguson also left Hernandez and Nani on the bench in a much-changed United team.
It looked like proving an expensive decision as Gerrard slotted a free-kick through the United wall to make it 1-0.
That was the signal for Ferguson to make changes - and Hernandez rescued a point with a close-range header.
Liverpool substitute Jordan Henderson almost snatched victory twice in stoppage time but United held on to end a run of three successive Premier League defeats at Anfield.
United were second-best for long periods as they struggled to adapt to an unfamiliar line-up and were ultimately fortunate to leave Merseyside with their unbeaten league run still intact.
And Ferguson was largely indebted to young keeper David de Gea, who has had his critics this season but made crucial saves to keep United in contention as they came under concerted pressure in the closing stages.
Ferguson, perhaps recalling how United had been comprehensively outfought in the 3-1 defeat at Liverpool last season, opted for a side with a more pragmatic look with Phil Jones moved into a midfield role.
And in an undistinguished opening, Jones had the best chance when he met Patrice Evra's cross at the far post but headed weakly off-target with what proved to be United's most inviting opening of the first half.
Liverpool captain Gerrard then created confusion in the United six-yard area with a whipped cross - but the clearest opportunity fell to Luis Suarez in the 33rd minute. Charlie Adam's shot deflected invitingly into the Uruguayan's path but, after cleverly wrong-footing Jonny Evans, he was thwarted by De Gea's block.
It was Liverpool who once again carried the momentum after the break and the recalled Rio Ferdinand was booked for a foul on Suarez, whose confrontational approach and brilliant natural ability was proving hard to handle.
After Evra was also shown a yellow card following a prolonged bout of bickering which also involved Suarez, Ferguson decided on a double change by replacing Park Ji-sung and Ashley Young with Nani and Rooney.
As they stood waiting to come on, Liverpool took the lead as Gerrard showed what his side have been missing. United hotly contested the free-kick awarded when Adam tumbled under Ferdinand's challenge - and Gerrard steered a 20-yard free-kick past De Gea, thanks in no small part to Ryan Giggs jumping out of the wall.
Ferguson then made another change as Liverpool moved within sight of victory, sending on Hernandez for Jones in the hope that the Mexican's goal-poaching instincts could be the catalyst for a comeback.
And so it proved when Hernandez arrived with perfect timing on to Danny Welbeck's flick from a corner to send a header flashing past Pepe Reina.
De Gea was United's hero again within seconds of Hernandez's equaliser, diving to his left to claw away Dirk Kuyt's shot as he got on the end of a superb cross from Stewart Downing.
Liverpool were still pressing for the winner in stoppage time with another substitute, Henderson, prominent. His angled finish was brilliantly turned away by De Gea and he also headed just over.
Defender Martin Skrtel should have done better than sky a chance into the Kop in the dying moments - and it was the Manchester United supporters who were happier with a point at the final whistle.