There is probably no fiercer rivalry in world soccer than the one between Real Madrid and Barcelona. The two Spanish sides are not only renowned for their respective greatness but also for their tremendous spending habits during transfer windows.

During 2013-14, both teams experienced differing results. Madrid won the Copa del Rey (beating Barcelona) before claiming Europe's highest honor for the 10th time in its history. Meanwhile Barcelona, which was the greatest side in the world in recent years, went through the season without a single major trophy.

Barcelona obviously sought out a change from its structural foundation and hired Luis Enrique to change the play style and imbue it with variety. In keeping with this team Barcelona went out and bought a number of players to bolster its roster. In came Marc Ter Stegen and Claudio Bravo to replenish the goal while Ivan Rakitic was brought in to add some depth to the midfield. Finally the team added a goal scorer in Luis Suarez to help take off some pressure from star man Lionel Messi. The team got rid of Cesc Fabregas and Alexis Sanchez while bringing back Gerard Deulofeu from his loan. Xavi Hernandez, who was expected to leave the side, has recently announced his return.

Meanwhile, Real Madrid went out and bought Toni Kroos and James Rodriguez. The side is expected to also bring in Keylor Navas any day now to fix its troubling goaltending situation. There have been no major departures yet but there could be an exodus of players including Sami Khedira, Isco, Karim Benzema, Angel Di Maria and Iker Casillas among others.

Both giants still have tremendous uncertainty however and there are major issues that must be resolved before either team can be given a winning grade. Barcelona addressed its center back problem with the addition of Jeremy Mathieu but, at age 30, he is far from a long-term solution. The goaltending situation is a solid one with Ter Stegen and Bravo both capable of taking over starting duties. Now the team must sort out its glut in the midfield. The return of Xavi is a problematic one as having the Spaniard around potentially forces the team to continue playing a weakened tiki taka style. Furthermore, it creates some roster issues. Where does Rakitic play? Where does Sergio Busquets fit in? Without Xavi, Andres Iniesta and Rakitic fit together in the middle alongside Busquets or Javier Mascherano (assuming he is not relegated to a center back again). But with Xavi, the midfield is too packed. Early in the season this should not be an issue as the absences of Neymar and Suarez will create roster flexibility. But upon their return, the team may have some issues to resolve.

Speaking of which... the forward three will be an issue for Enrique to overcome. Suarez, Neymar and Messi are all superstars but there will have to be some delegation among the three. Who becomes the main target man? Who takes free kicks? Penalties? Can these men keep their egos off the pitch and work together? Will Messi play behind Suarez or on the wing? These questions will provide the greatest concern for Barcelona's coach this season.

Madrid has its own plethora of concerns. The team brought in two attacking players on a team that had no problems with goalscoring. Rodriguez is best utilized behind a striker, thus forcing Carlo Ancelotti in a 4-2-3-1 formation with Benzema as the target man. The problem concerns the two behind Rodriguez. Kroos, Xabi Alonso, Luka Modric, Khedira and Di Maria can all slot into the midfield, but only two would get the chance if Rodriguez starts. And these issues do not even consider what the future holds for youngster Isco and Jese Rodriguez. Where do they go? Will Madrid bench them, sell them or loan them out?

Kroos and Rodriguez were brought in this summer and it is likely that both will get to start. If Modric is the man selected to play in the middle three with them, then it is likely that Khedira and Di Maria are on their way out. Alonso at 32 is probably best on the bench, but then comes the greatest problem of all. Without Di Maria or Alonso (or even Asier Illarramendi) on the pitch, Madrid has no holding midfielder that can help win the ball back. The team would be exposed down the left flank with Cristiano Ronaldo likely not tracking back and Rodriguez caught in the middle. The team would be very susceptible to attacks in the midfield and would rely heavily on its back four to quell major attacks. Marcelo is no defender (as evidenced in the World Cup) while Sergio Ramos also has his poor moments. This is an issue Madrid must still consider because it is not one that can be bought. Even by selling players and playing a holding player on the pitch, coach Carlo Ancelotti will be forced to bench a top player. And that could harm the ambience within the team.

Looking at the two sides, Barcelona has obviously helped itself moving forward and adding depth in the attack. But the center back position remains a concern and will determine the success of the squad moving forward. For Madrid, the additions are certainly grabbing headlines but they might not really be a massive improvement and could actually hurt the team's unity from last season. Ancelotti managed to field a perfect midfield trio behind its top attackers and created great balance. Now he will be tested to find the same mix and get the side to continue its winning ways.

Barcelona looks like an early winner, but the transfer window is still weeks away from closing and both sides could easily address their major issues.