After the storm came the drought. This was a contest that featured a seven-goal avalanche inside 35 minutes but then fell barren, though was still unmissable.
If it was the kind of pell-mell exchange all managers hate and neutrals love, the first-half count should have actually been eight – to break the record – but Robin van Persie's strike near the break was ruled out wrongly.
To the chagrin of Alex Ferguson, his team conceded the opener for the 14th time this season as the breathless 26 minutes began. Eight had been played when this leaky United defence allowed Jay Tabb to turn the ball out to Jobi McAnuff and, when the captain swung in a cross, Jonny Evans's header went straight to Hal Robson-Kanu; his left-foot volley beat Anders Lindegaard via a deflection from the Northern Irish defender.
The first of United's two equalisers in this sequence came when Michael Carrick found Anderson, who moved the ball on to Ashley Young and, when the Brazilian continued running, he received the return before blazing a rocket past Adam Federici. Anderson's celebration featured a dance move that was a kind of strutting tap-dance on the spot.
This was after 13 minutes. Within 90 seconds Wayne Rooney had given the visitors the lead.
From the Liverpudlian's corner Evans did well to control the ball and, as he brought it down, Tabb, for some reason, decided to barge him over. From the spot, Rooney beat Federici to the goalkeeper's left for a fourth of a so far hardly prolific season. Now came two Reading goals, both unmarked headers from corners.
This was simple, schoolboy stuff but United could do nothing to repel either. First, Nicky Shorey's 19th-minute delivery found Adam Le Fondre and with Rio Ferdinand wandering the No 9 finished. Then Sean Morrison produced a carbon copy, rising to meet Shorey's kick on 23 minutes to give Reading a barely credible 3-2 lead.
By the time the clock showed 34 minutes played it would be 4-3 to United, and Rafael had first been booked, then hooked by Ferguson (on 28 and 31 minutes, respectively), the Brazilian seeming to ignore his manager's conciliatory gesture to sit down and embarking on a sulky pout he still wore as half-time approached.
When the sides walked off at that juncture United's advantage had come from two slick moves, though, as throughout the game, lax defending played a part. A Patrice Evra pass to Young became a one-two when the winger executed a backheel to his skipper, whose cross from the left allowed the unmarked Rooney to score his second.
Then Rooney created Robin Van Persie's 13th of his debut United season. Carrick's measured pass was deftly flicked on sideways by the forward and Van Persie, with his lesser-used right boot, slid the ball beyond Federici.
That was it for the period, though Van Persie had a case for a second when a header from Chris Smalling, on for Rafael, rebounded to the Dutchman and his close-range finish appeared over the line before it was cleared by Adrian Mariappa.
After Ferguson's pre-match exhortation to Rooney to score more, it was a surprise to see him on the right of the 4-2-3-1 decided upon by his manager.
This is virtually a collector's item and when Anderson, who was playing in the hole, was replaced by Phil Jones before half-time, he stayed there and continued to be influential. Early in the second half, it was Rooney who took charge of a United free-kick and, later, his ability to drift into space nearly created United's fifth before Darren Fletcher over-elaborated in the penalty area.
Yet, as with Van Persie, he was required to defend as Ferguson's midfield shield of Carrick and Darren Fletcher continued to struggle to slow this open game down.
Mark Halsey looked correct when turning down a penalty appeal for an Evra challenge on Mariappa – he took the ball – but Federici's was the wrong option on 66 minutes. The keeper's attempted dribble past Van Persie handed the ball to him and the striker just missed from close range.