Nemanja Vidic’s header gave the hosts the lead from a corner in the 58th minute, before Bastian Schweinsteiger’s superb half-volley pulled the visitors level in the 66th minute.
Schweinsteiger was later sent off for a second bookable offence as the draw set up an intriguing second leg in Munich next Wednesday.
Tuesday’s clash prompted plenty of reaction on Twitter – and here are our favourite updates, in chronological order.
Ex-goalkeeper Edwin van der Sar (@vdsar1970) wishes United all the best: “Good luck to the boys tonight and hope for better outcome then games we played in 2010 in quarter final #MUFCBAYERN keep an eye on Robben!”
England legend Gary Lineker (@GaryLineker) appears to be enjoying watching Arjen Robben at Old Trafford: “Robben is as dangerous as he is irritating!”
Former United striker Louis Saha (@louissaha08) is distraught as Danny Welbeck misses the first big chance of the game: “What a chance dannyyyyyyyyyy!!!! Come on #ManUtd”
Ex-Man Utd defender Viv Anderson (@Anderson_Viv) is happy with the half-time result: “I would have took 0-0 at half time, could be 1-0 up but thats football. See what the second half has to bring”
Former Netherlands international Mario Melchiot (@MarioMelchiot) chimes in as Vidic nods United in front: “Goal Vidic!!! I really didn’t expect that but that’s why football is the best game there is. So unpredictable! #ManUtdBayern #mmlove”
Ex-United defender Gary Neville (@GNev2) laughs at his own joke: “Barca losing. It’s opening up for United!! Hahhahahhaaha”
Former Stoke City man Danny Higginbotham (@Higginbotham05) chimes in: “Great performance so far from united. Starting to stretch bayern by keeping Rooney and either welbeck or Valencia up field depending on side”
Manchester United goalkeeper Ben Amos (@Amos_40) is a happy man: “Gutsy. Disciplined. Dogged. What an effort against a top team #SeeYouInMunich”
Defender Rio Ferdinand (@rioferdy5) is buzzing: “Another great European night under the lights at old Trafford…amazing support & atmosphere! Thank u!! Roll on Wednesday !!”
As is goalkeeper David De Gea (@D_DeGea): “Great atmosphere in Old Trafford!!! Thanks again for your incredible support! You’re the best. Look forward to 2nd leg. #MUFC”
And United coach Phil Neville (@fizzer18) has the final say: “Good performance from the team great spirit and determination – atmosphere was brilliant again well done”
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