Year in and year out, the world expects a surprise. And yet every year, the same teams continually make reappearances in the latter stages of the Champions League.

However, for once, the 2014-15 UCL is threatening to show a new level of excitement as the first host of matches have featured some tremendous shockers.

Real Madrid and Barcelona continued their winning ways in this tournament, the latter doing so at the expense of a suddenly mediocre Manchester City.

But there were some other puzzling situations that have left the second legs with tremendous amounts of tension. Here are some of the big shockers of the UCL round of 16's first legs:

Bayern Shut Down At Shakhtar

Raise your hand if you thought Bayern would dominate this tie (And by dominate, I do not mean in possession)? That should be everyone. And yet, the champs from two years ago enter their fateful second leg tied a 0-0 and facing a team that looks as confident as ever. Bayern remains the favorite at home, but the team has struggled in 2015 with an 8-0 victory the lone outlier in a laundry list of mediocre performances.

More importantly, Xabi Alonso, the essential piece in the midfield will be out of this tie, leaving the team to adjust its midfield in his absence.

The 0-0 draw was obviously the result of losing Alonso to a red card, but without him the team will have to answer some crucial questions moving forward. He was the man to make the midfield run.

And without him, this team might be lacking the versatility in attack that had made it such a dominant workhorse earlier this year.

Atletico Run Down At Leverkusen

Last year's runner-ups have admittedly seen better days and worse days. A 1-0 loss in Germany is not the worst thing in the world, but it puts Diego Simeone and company in dire straits. What do you do in the second leg at home?

Do you run rampant on Leverkusen and remain open to the counterattack (which one might note is not a good strategy for this team)? Or do you play the usual sitting back and waiting to attack on the counter or hope for a few corners to get some goals going from the air?

It is not the worst situation to be in as a goal ties up the match-up and puts this team right back into the contest. But Atletico might now have to take on a resurgent Leverkusen side that has been solid throughout.

Arsenal Implodes Yet Again

Against such teams as Bayern Munich and Barcelona, one would have to give Arsenal a pass in the UCL round of 16. But against Monaco? It is becoming increasingly worrisome that this team simply has no idea how to manage the stress of playing its first leg at home. The team lost by two goals in the last two years again Munich and repeated the infamous feat against a Monaco side that can afford a 2-0 loss in the second leg.

More troubling is that when the team battled back to win a goal in the dying minutes, manager Arsene Wenger did not gather in his troops, accepts the 2-1 loss and live to play for a doable 2-0 win on the road. Instead, the team chased the 2-2 draw and wound up giving up the 3-1 tally in the waning SECONDS of the match. The team went after a tough feat and wound up with mission impossible on its hands.

Manchester City's Mediocrity

What is most shocking is how people continue to be surprised by Manchester's mediocrity in this competition. Always a perennial Premier League contender, the Citizens have a knack for finding new lows in Europe's top flight. Barcelona is undoubtedly a tough rival, but Manuel Pellegrini's squad looked utterly helpless in the opening half where Barcelona built an stranglehold 2-0 lead. The team simply lacked the intensity or even legs to keep up with Barcelona's passing game or even pressure it.