United were pathetic in the first half and superb in the second... but it took a silly mistake from an 18-year-old debutant to break the deadlock - a defence that was superbly marshalled by Luisao and Ruben Dias deserved better... but such is the way of the world. Poor Mile Svilar will only learn from such bad experiences... onwards and upwards, young man.
Manchester United maintain their 100% record and their stranglehold at the top of Group A; Benfica remain stranded at the bottom.
That's all from me tonight. Thank you for reading... Anirudh Menon signing out.
92' OH HO! LUISAO GETS SENT OFF FOR FLYING INTO McTOMINAY! He had done superbly to block Lukaku initially, but the follow-up foul was simply idiotic. Benfica will miss him at Old Trafford
91' Valencia smashes one into the box in typically forceful style, but Slivar catches well. Meanwhile, Mourinho gives Scott McTominay a run out in the Champions League as he takes off the disappointing Henrikh Mkhitaryan
89' Jimenez sends one in speculatively but a Blind miscue allows Cervi to win a corner off Herrera. This time the corner is nodded away by Valencia and Grimaldo's followup flies well wide
87' OH RUBEN DIAS, TAKE A BOW, YOU BRAVE MAN! United counter at supreme pace through Martial, but the centre-back does ever so well to keep up with the flying Frenchman and nick the ball off him
86' Benfica win another corner as Cervi runs at Herrera... Smalling thumps this one clear. Cervi sends it back with interest, but Herrera rises high to thump it clear this time
85' WOOF! Martial's insanely quick feet work some space where there ought to be one inside the Benfica box before he tees up Mkhitaryan, who is in turn closed down superbly by Ruben Dias
84' Cervi's first contribution is to win a corner... from which Ruben Dias sends a flying volley into row Z! That was a difficult chance, but a chance nonetheless. Mourinho will be furious that the big centre-back was left unmarked in the box!
81' Herrera who has been brilliant this half wins the ball back inside his own half and plays it on to Martial, but the Frenchman's attempt to link up with Mkhitaryan is well read by Luisao. Zivkovic curls one into the box at the other end, but Smalling sends it clear with a spectacular header
79' Unfortunately for them, the corner is straight at Lukaku. United move forward purposefully and Lukaku swings it to Martial..... the Frenchman does what he does by sending Douglas to another postal code and racing into the box... he opts to try and beat Svilar from close range but the young keeper does well to keep the score at 1-0
78' Benfica are certainly not out of this yet and Jonas wins a corner with a shot that's deflected off Lindelof. The crowd are trying their best to get behind their team.
77' Martial's first bit of action is to smash one into Lukaku's chest, who in turn tries to tee up Herrera, but the Basque can do naught but win a corner in the face of some superb defending from Ruben DIas
74' Grimaldo pings one into the box and Lindelof heads it clear well. This has been the Swede's best display yet in a United shirt... returning to Lisbon has certainly worked for him. Rashford, meanwhile, has gone to ground feeling his legs... he's probably going off now
71' Cries for handball as Zivkovic's pass is stopped by a prone Valencia (who'd slipped on the way to blocking him) but the ref waves play on... Benfica come back in numbers and Jonas turns on a dime and shoots at goal, but nothing doing
70' OH LUISAO! The big Benfica captain does ever so well to keep pace with Rashford, steal the ball from his toes and pass it out of danger. Him and Dias have been absolutely splendid tonight
69' Benfica, chasing that all-important goal now, throws on Jonas for a tired looking Diogo Goncalves. Benfica's faithful will be looking to their talismanic striker for a couple of goals now. But a Mourinho defence is the worst to play against when seeking an equaliser, isn't it?
61' OOHOHOHOHO AGAIN! Rashford tries another Olimpico that has Svilar scrambling to claw away! That really was close! The third corner is played flat and wide and is useless
59' Benfica make their first change as Vitoria takes off Pizzi and flings on Zivkovic in an attempts to get more energy into those Benfica legs.Meanwhile, United win a corner off Douglas
58' Herrera battles his way past a couple of challenges in a way that always endears him to the United faithful before laying it off to Matic who absolutely leathers one just over the Benfica goal!
57' Rashford plays the ball to Lukaku, who in turn tries to bully his way past four red shirts, but the Benfica lads hold their ground supremely well. Seriously, 5-0 to Basel?
55' Valencia bursts into the Benfica third and whips in a cross that curls behind Valencia and Mkhitaryan... Benfica counter at pace and Pizzi's ball almooooost finds its way to Jimenez but the ball just had a touch more pace than the Mexican striker
54' It's a delightful ball in that's well headed away by Smalling... Rashford runs onto it and breaks into the Benfica half... Goncalves sees the danger, puts two hands on the back of Rashford's collar and puls him down with the minimum of ceremony. Yellow for the Benfica lad.
53' To think this side lost 5-0 at Basel. Rui Vitoria's made sure his defense has collectively learned their lesson here! Meanwhile, moving forward Matic gives a freekick on Pizzi, and the playmaker himself will look to swing it in to the area...
52' OOO LA LA! Rashford makes an absolute mug of Douglas down the United left but he can't quite make enough of the move. Blind then tries to curl one onto Lukaku's noggin' but Svilar does ever so well to read it, come out, and grab it.
51' WOOF! Rashford smacks one at Svilar, but it's straight at the Belgian and he does well to handle it. United are stepping up the pressure here... till Matic's ball into Mata is a tad off and it rolls out for a goalkick
50' OH! OH! Savio steams past Blind on the United left and smashes in a lovely little cross that is defended supremely well by Valencia who smacks it clear ahead of a lurking Raul Jimenez
49' United have started at a far greater tempo this half, on and off the ball and some incessant high pressing wins them the ball back after a spell of Benfica passing only for the Portuguese giants to get it back via throw in
47' OH! Rashford flies into the Benfica box, but once again that perfect high-line does the trick. At the other end Diogo Goncalves smashes one into the stands from twenty odd yards
46' Blind plays in Rashford who squeezes Benfica back before passing it to Mkhitaryan, who in turn lays it off to Herrera - the Basque sends it spiralling into the night sky
Benfica have defended smartly, attacked energetically and have generally looked a better side than sloppy Manchester United. Mourinho will be absolutely furious with his players for the ease with which they often gave up possession. I suspect the hairdryer may be dragged out in the away team dressing room for the next fifteen minutes.
44' Mata tries to unlock the high-line with a lovely looking reverse pass that finds Blind onside. That's poor from the Dutchman, he should have timed that run better