A difficult night just got tougher for Arsenal after Danny Welbeck pulled up injured minutes before kick-off.

Here come the teams...

Bad start for Arsenal - and a ball has not been kicked in anger.

Danny Welbeck, who was in the starting line-up, has been injured in the warm-up and Olivier Giroud, originally named as a substitute, takes his place in the side.

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Phil McNulty
BBC Sport chief football writer

A blast of David Bowie's "Heroes" over the PA here - wild optimism but Arsenal's players certainly will be heroes if they can pull off this comeback.

Image source, Rex Features

Matthew Broad:  Forget early, my dad once got us to a non-league match at 3pm on a bank holiday. It kicked off at 1:30! #Saw15Mins, external

Paul Hossack:  I turned up 24 hours early to a Sheffield United game. Forgot the game had been moved to Sunday...

Mark Suileabhan: Four hours used to be normal in the days of the Kop and paying on the turnstile. In at 12 for 3 kick-off.

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It will require a monumental effort if Arsenal reach the quarter-finals for the first time since 2009-10.

This is the eighth meeting between the Gunners and Bayern Munich in the last four years. 

Arsene Wenger has tasted two victories and four defeats with Arsenal losing the last two 5-1.

Jay:  Arsenal protesters are behaving like amateurs. Don't they know that protests without a flying banner aren't taken seriously?

onsideVIEW:  Those "fans" protesting are clueless. All kids who probably couldn't tell you the previous manager or last title before Wenger.

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BBC Three

As Welsh band Stereophonics once sang: "There's no mistake, I smell that smell, it's that time of year again", and that's how Arsene Wenger must be feeling.

It's Champions League last-16, second-leg time, which means Arsenal once again have their bags packed, ready to get knocked out of the competition.

After losing their first leg 5-1 away at Bayern Munich, the Gunners need a miracle if they are to avoid leaving Europe's top club competition at this very stage for the seventh straight season.

If Arsenal don't win, then just like Bill Murray in the classic film Groundhog Day, Arsene Wenger will feel like he's living the same day again and again and again....

Neil Lennon
Hibernian manager on BBC Radio 5 live

I think Arsene Wenger is finished at Arsenal. I don't want his legacy tarnished. It's groundhog season for Arsenal. What they want to be doing is challenging for the Premier League.

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In honour of the 20,000 Napoli fans who arrived five hours before kick-off for tonight's game against Real Madrid...we want to know the earliest you've turned up for a sporting fixture and why?

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Steve Wing:  I hitched from Sandbach to Portsmouth to watch Bideford AFC play in the 1st round FA Cup. Arrived in Pompey at 3am. Lost 3-1!  

Michael MacLean:  Got to Murrayfield at 4am in Feb '06 for Calcutta Cup tickets, totally worth it as we won.  

Karen Fazackerley:  Slept overnight outside Turf Moor to get my hands on tickets for the Championship play-off final at Wembley - well worth it! 

Jermaine Jenas
Former England midfielder on 5 live

I'm sure it's getting boring for Arsenal fans. The same situations keep cropping up each year - injuries to important players, getting knocked out in the last 16 of the Champions League and no genuine league title challenge.

The game tonight is beyond tough. They need to put in a performance with a more positive mindset than they've had in the past few months. 

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Image source, Rex Features

Arsenal are 33-1 to overturn a 5-1 first-leg thrashing by Bayern Munich and progress to the Champions League quarter-finals.

How do some other unlikely events compare? Take a look here. This just might surprise you.

Arsenal

Arsene Wenger is demanding a performance full of pride and honour after the embarrassing display in Germany.

"What is at stake is our pride and our honour to really compete for 90 minutes," the Frenchman writes in his programme notes.

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BBC Radio 5 live

Arsenal fan Mark King, speaking to BBC Radio 5 live about the protest march by supporters ahead of tonight's game:  "We were told we were moving from Highbury to the Emirates to compete with the likes of Bayern Munich. It doesn’t seem like that’s the case.

"We just want to do a nice respectful march and suggest that the club should not be giving Arsene Wenger a new contract because he hasn’t actually done anything to merit it.

"I think he wants a new contract – he’s nice and cosy at Arsenal, nobody really gives him a hard time, certainly no one that employs him and pays him.

"He doesn’t really care too much for what the fans say so I think he’d be more than happy to carry on."

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Phil McNulty
BBC Sport chief football writer at Emirates Stadium

A small group of Arsenal fans gathered outside the stadium before kick-off armed with banners and also chanting "Arsene Wenger - We Want You To Go."

It could hardly be described as a mutinous atmosphere but it was certainly an indicator, albeit a small one, of the feeling of unease and discontent currently surrounding the club and its manager.

Image source, Getty Images

Image source, Getty Images

Arsenal

He's won three Premier League titles, six FA Cups...and he once took Arsenal to the Champions League final.

But is Arsene Wenger's 21-year reign as Arsenal boss coming to an end?

This is his 184th Champions League match in charge of the Gunners...and possibly last.

Some fans are not happy and have even taken to the streets before tonight's game to make their point.

Image source, EPA

Phil McNulty
BBC Sport chief football writer at Emirates Stadium

No holding anyone back tonight - Arsenal need goals so Alexis Sanchez starts after being contentiously dropped to the bench at Liverpool. Chance for him to work out his frustrations on Bayern Munich.

Sanchez is presumably under orders from Wenger to get at least four goals.

Arsenal keeper David Ospina, Theo Walcott, Alexis Sanchez and Aaron Ramsey come into the starting XI. Midfielder Mesut Ozil has recovered from an illness to take his place on the bench.

Bayern Munich's defensive player Phlipp Lahm is suspended for the return leg and is replaced by Rafinha. Midfielder Franck Ribery returns to the starting XI in place of Douglas Costa.

Arsenal XI:  Ospina, Bellerin, Mustafi, Koscielny, Monreal, Oxlade-Chamberlain, Xhaka, Ramsey, Walcott, Sanchez, Welbeck.

Subs: Cech, Gibbs. Ozil, Coquelin, Giroud, Lucas.

Bayern XI: Neuer; Rafinha, Hummels, Martínez, Alaba; Alonso, Thiago, Vidal; Robben, Ribery, Lewandowski. 

Subs:  Ulreich, Costa, Bernat, Muller, Coman, Kimmich, Sanches.  

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Gareth Bale and Cristiano Ronaldo return to Real Madrid's starting line-up as the Champions League holders select an attacking XI.

Bale was suspended for Madrid's La Liga victory over Eibar at the weekend and Ronaldo has recovered from a minor injury.

The Portugal captain is just five off a century of goals in the Champions League and he has an impressive record in the last-16 - 14 goals in the last five seasons at this stage.

Napoli winger Dries Mertens starts after recovering from a knock in Saturday's 2-1 win over Roma.  

Napoli XI:  Reina, Hysaj, Albiol, Koulibaly, Ghoulam, Allan, Diawara, Hamsik, Callejón, Mertens, Insigne.  

Subs: Rafael Cabral, Jorginho, Maggio, Maksimovic, Zielinski, Rog, Milik.

Real Madrid XI:  Navas, Carvajal, Pepe, Sergio Ramos, Ronaldo, Kroos, Benzema, Bale, Marcelo, Casemiro, Modric.

Subs:  Kiko Casilla, Nacho, James, Lucas V, Morata, Isco, Danilo.

Image source, Getty Images

On the back of Napoli fans taking their seats very, very early for their match with Real Madrid, we want to know the earliest you have turned up for a football match - and why?

Have you camped overnight to secure a ticket for a vital cup tie? Have you been the first to arrive at a ground?

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