Cristiano Ronaldo salvaged a point for Manchester United and denied Reading an historic win at the Madejski Stadium.
Ronaldo shows his joy and relief
Ronaldo cut inside from the left to unleash a shot across Marcus Hahnemann to spare United's blushes.
Kevin Doyle earlier fired Reading ahead from the penalty spot after referee Peter Walton ruled Gary Neville handled Seol Ki-Hyeon's cross.
United had chances to steal the points, with Kieran Richardson missing his kick in front of goal.
Gabriel Heinze lined up for the first time in over a year in a Manchester United team that showed five changes from that beaten by Arsenal.
They almost snatched an early lead as Wayne Rooney's shot on the turn proved too hot for Hahnemann to hold and Graeme Murty just got to the loose ball ahead of the prowling Richardson.
By his own admission, Rooney is yet to find his touch this season and that was evident as Ronaldo's cute pass found him in space inside the box but the England striker's underhit shot proved little trouble for Hahneman.
Hahnemann continued to give the impression he wore non-stick gloves as he spilled Ronaldo's free-kick and Ivar Ingimarsson's clearance bailed him out.
In contrast, Van der Sar's handling was clean as a whistle as he went down to clutch Ki-Hyeon's powerful low drive with Leroy Lita lurking in vain for scraps.
Kevin Doyle is swamped by joyous team-mates
United, though, always carried more menace and when Ronaldo got to the dead-ball line he fired across the face of goal with Paul Scholes just failing to make contact.
Reading, defending a 100% home record, worked like Trojans to deny United space on the flanks and the lack of width forced the visitors to try and pick their way through the middle where Reading always ensured there was congestion.
Reading went ahead soon after the restart in controversial circumstances. Referee Walton ruled Neville controlled Ki-Hyeon's cross with his upper arm, a decision replays suggested might have been harsh to say the least.
Van der Sar guessed right and got a hand to Doyle's penalty but was unable to keep it out as the Irish striker claimed his fourth goal of the season.
Reading were not content to sit on their lead and the mobility of Lita and Doyle along United's back line kept them stretched.
Richardson completely missed his kick in front of goal from Rooney's cross, and he was instantly replaced by Saha as Sir Alex Ferguson looked to give Rooney more support.
United needed something inspirational to crack Reading's resistance and they got it from Ronaldo who collected the ball wide on the left, weaved his way inside Murty and fired an angled shot across Hahnemann.
The goal changed the face of the game, and United poured forward in search of a winner, but Reading continued to defend heroically, and held out for a deserved point.
Reading boss Steve Coppell:
"I thought it was going to go our way, but there was a piece of individual skill and a great finish from Ronaldo.
"So we're half-pleased with the point given how the game went, thinking what might have been.
"I have to give my players a round of applause for their efforts."
Manchester United boss Sir Alex Ferguson:
"Reading, they fought for every ball and worked their tails off. But we should have done better.
"They put eight bodies in front of us in their box and that is not easy to play against.
"We had shots blocked, over the bar and the keeper made two or three good saves. Sometimes it happens that way."
Reading: Hahnemann, Murty (Bikey 89), Sonko, Ingimarsson, Shorey, Ki-Hyeon (Hunt 85), Sidwell, Harper, Convey, Lita (Gunnarsson 76), Doyle.
Subs Not Used: Stack, Long.
Goals: Doyle 48 pen.
Man Utd: Van der Sar, Neville, Vidic, Ferdinand, Heinze (O'Shea 70), Fletcher (Solskjaer 70), Carrick, Scholes, Richardson (Saha 58), Ronaldo, Rooney.
Subs Not Used: Brown, Kuszczak.
Goals: Ronaldo 73.
Ref: P Walton (Northamptonshire).