Sir Alex Ferguson could be forgiven for having sleepless nights about the way his team collapsed after Welbeck's first goals in Europe seemed to have put them in control of this Group C tie.
'I never look back, tomorrow's another day for me,' he had said in the build-up to this game, and maybe it's for the best.
Heads I win! Young heads United level in the 90th minute
MATCH FACTS Man United: De Gea, Fabio Da Silva (Nani 69), Jones, Ferdinand, Evra, Anderson (Berbatov 82), Carrick, Giggs (Park 61), Valencia, Welbeck, Young.
Subs not used: Lindegaard, Owen, Fletcher, Diouf.
Goals: Welbeck 16, 17; Young 90
Basle: Sommer, Steinhofer, Abraham, Dragovic, Park, Fabian Frei (Chipperfield 76), Cabral, Zoua, Granit Xhaka, Alexander Frei (Taulant Xhaka 89), Streller (Pak 80).
Subs not used: Colomba, Ajeti, Schurpf, Kovac,
Booked: Frei, Xhaka
Goals: F Frei 58, A Frei 60, 76 pen.
Referee: Paolo Tagliavento (Italy)
How United found themselves moments away from losing at home in this competition for only the second time in33 games only they will know, but they were grateful to Young for rescuing them on his Champions League debut.
A second successive draw leaves United precariously placed in what looked like a straightforward group. Two points from two games is poor by their standards, and they face a difficult trip to Romania to face Otelul Galati in December.
What will concern Ferguson most is that the warning signs were there long before Alexander Frei and namesake Fabian Frei struck three times in 18 second-half minutes.
It had all begun so well after his decision to start with Welbeck and leave Dimitar Berbatov on the bench. With Wayne Rooney and Javier Hernandez injured on the sidelines, this had been seen as Berbatov's big chance to prove he can still score in big games.
Instead, after a run of 20 Champions League appearances stretching back almost three years without a goal, hewatched 20-year-old Welbeck score twice in 80 seconds.
Brace yourself: Welbeck bagged two goals inside 60 first-half seconds
It was a magnificent response from the young England striker and only served to highlight Berbatov's deficiencies on the European stage.
Welbeck's first goal in the competition was hardly a classic. Antonio Valencia slipped the ball to Fabio da Silva in the 16th minute and the Brazilian squared it to the edge of the six-yard box.
Ryan Giggs touched it back for Welbeck whose slightly scuffed effort took a deflection off Markus Steinhofer as it crept in.
Spot on: Frei gave Basle the lea as the Swiss side sensed an upset
Opportunity knocked again for Welbeckas Basle's defence switched off when Giggs floated to the edge of the penalty area. His angled ball into the middle found Welbeck in yards of space and this time his first-time finish was much more assured from eight yards out.
Basle had already wasted one clear chance through Fabian Frei when Alexander Frei somehow side-footed wide with only David de Gea to beat and Jacques Zoua scooped his effort off target from another promising position, leaving coach Thorsten Fink beating his seat in frustration.
Ferguson's hands were tied, however. Injuries to key defenders meant the bench was packed with forwards and his options were limited as United continued to rock unsteadily after the break.
Frayed nerves: United fans looked anxious until Young scored the late equaliser
De Gea stuck out a foot to turn MarcoStreller's shot over the bar from point-black range but United's goalkeeper was beaten twice in as many minutes as the Freis made amends for earlier misses.
Fabian reduced the deficit in the 58th minute, firing in off the post from the edge of the area after De Gea had palmed away Streller's flick header from a corner.
And United were opened up again almost immediately as the goalscorer turned provider, breaking down the right and sending over a precise cross that evaded Rio Ferdinand and picked out Alexander Frei, who headed the ball back across goal and intothe net.
Plenty to ponder: United displayed a number of defensive frailties which were exposed by Basle
If United thought that Basle would behappy to emulate the draw they picked up on their last visit to Old Trafford in 2003, they were mistaken.
The visitors continued to press and, when Phil Jones played Valencia into trouble rather than clearing his lines 14 minutes from time, the Ecuador winger lost possession to Streller then was judged to have fouled Basle's No 9 as he tried to win back the ball.
Ferguson did not think it was a penalty but Italian referee Paolo Tagliavento did, and Alexander Frei beat De Gea from the spot. Fink knows the script, though.
The Basle coach was a Bayern Munich player in 1999 when United staged that memorable comeback in the Champions League final, and it took until the 90th minute for Young to grab the equaliser, meeting Nani's deep cross with a downward header inside Yann Sommer's near post to add the final twist to a fantastic game.
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