Champions League draw reactions
"I would have liked to have played against United later in the competition but they won't be pleased either," Emilio Butragueno, former Real striker now a club director, told Spanish broadcaster Canal Plus.
"It will be a fantastic tie for the fans and the players. It's an honour to play against such a prestigious team.
"We hope to go into the match in good condition and with all the players fit again.
"Preferences (for an opponent) are irrelevant. You have to prepare well. It's a stimulus for the players, the fans and the club. We have to make the most of the expectation."
"Everyone wanted to keep this for later in the competition but, out of several stand-out ties, I think this is the one. If history has anything in our favour our one victory against Real Madrid in this competition was in the season when we won the final at Wembley," Manchester United club secretary John Alexander told Sky Sports News.
"Milan are one of Europe's greats and a club that commands a huge amount of respect," Barcelona vice president Josep Maria Bartomeu told Spanish broadcaster Canal Plus.
"Such a great name is intimidating but we will approach the tie with the highest of hopes. They are not going well in their league right now but they have some excellent players.
"They are not currently at their best but football changes from one day to the next. We have to pay them a huge amount of respect and try to be in good condition in time for the tie."
"We know Arsenal well. We can be satisfied with the draw, but we mustn't underestimate them," Bayern chairman Karl-Heinz Rummenigge said on the club website (fcbayern.telekom.de).
"It's important we try to come away from London with a good result, score a goal there and lay down a marker. We can win it, and we start as favourites."
Paris St Germain
"It's always difficult to say whether it's a good draw or not. In the Champions League, it always depends on the moment you play the game, the run of form," Paris St Germain director of football Leonardo told French TV channel beIN Sport.
"There are great teams left and we have incredible European classic ties in the last 16. We are going to have a difficult encounter with Valencia who are an experienced side."
"If we have got this far it's because we are among the 16 best teams in Europe," Valencia director Fernando Giner told Spanish broadcaster Canal Plus.
"PSG are a tough opponent. We have to be satisfied to be here and it's a way of coming together at a difficult moment to achieve the result we all want.
"During these difficult times the Champions League is tremendously exciting for us.
"The tie will help us relive some of the Champions League moments of a few years ago."
"In terms of glamour it is great," Celtic manager Neil Lennon tells Sky Sports News.
"In terms of qualification it is going to be very tough. But we will take it as it comes and our supporters will be looking forward to this match. Juventus are littered with world-class stars and they have been very consistent over the last 18 months.
"But coming through the group as impressively as we did, and you never know where you are going to be in a few months time. This club is built on the legends of Jock Stein and the Lisbon Lions, this team is reaching those same heights again. They have belief in themselves and have been playing very well away from home."
"We knew that, whatever team we faced, it would be tough. Juventus have a young, talented side and a good mix," Celtic assistant manger Johan Mjallby told Reuters in a telephone interview.
"Maybe they didn't completely dominate their group, but it was still strong to qualify. They look impressive in their league and it's a side we have great respect for.
"But if I remember rightly, we've only lost two matches of 23 at home in the Champions League and both of those were against Barcelona. That tells us that we can give any team a game on our home pitch."
"They (Porto) are a fantastic team. They are playing very well and it's going to be very hard to get past them but we will go after them," Malaga director Francisco Martin Aguilar told Spanish broadcaster Canal Plus.
"They were not the team we expected or wanted. They are the strongest side we could have drawn.
"They are a great team and we have to approach the tie with the same excitement and desire we have shown throughout the Champions League this season."