Lionel Messi is injured.

That is bad enough, but what is more concerning is that to this point no one seems to know what is wrong with him. And because of that, the future seems a bit uncertain for his club Barcelona.

Let's take a few steps back. According to sources, the superstar, who was enjoying his best play since 2012, was suffering from an injury that he obtained during the Clasico against Real Madrid two weeks ago. That injury left him out of both friendlies for Argentina during the International Break.

But what is worse is that now that injury, which was supposed to be minor, is now keeping him out of this weekend's upcoming game against Celta Vigo.

Celta Vigo, of course, defeated Barcelona when the two sides convened at the Camp Nou a few months ago. And despite that game featuring Messi, it also featured a struggling Barcelona side. The team will not be struggling heading into this game, but without Messi it could be in for a world of hurt.

But is Barcelona better without Messi?

Last season was actually rather interesting in that respect. In the first half of 2013-14, forwards playing with Messi managed 13 goals and 14 assists in a combined 48 games played. Forwards included in this analysis included Cesc Fabregas, Neymar, Pedro and Alexis Sanchez. Without Messi, these players scored 35 goals and 17 assists in a combined 55 games. That is a massive difference, but it speaks to how valuable Messi is in leading the offense for Blaugrana.

But this season is a bit different as Messi has scored 20 goals in 2015 across all competitions for Blaugrana. And his scoring has helped Luis Suarez and Neymar reach greater heights. Together, the trio has scored an astonishing 55 goals in 2014-15, 32 of which belong to Messi himself.

Throw in the fact that the superstar has a whopping 15 assists on the year (more than anyone else in the entire league!) and you have a major issue in the attack. Suarez has nine assists, but more than a handful have been to Messi himself. Messi also creates more key passes than anyone else in the entire league (2.6 per game) and he is also the through ball king in Spain with almost one per game. He is second in the league on shots on goal (Cristiano Ronaldo leads the way), but he has more goals than his rival, thus establishing that he takes advantage of his chances. He is the best dribbler in the league.

Essentially, Messi generates more offense than any other player in the entire Spanish League.

This is nothing new, but for Barcelona, it is huge. Without its top offensive generator, the team certainly loses a few steps and, against a decent Celta Vigo side, the uphill battle might be tantamount.

Suarez puts up 2.2 key passes per game, which is comparable to Messi, but everyone knows that what has made Suarez grow this year with the club has been Messi's generosity towards the Uruguayan. Neymar, meanwhile, has an average of 1.3 key passes per game which would not make up for Messi's absence. Pedro, Messi's likely replacement, is barely averaging one key pass per game.

Barcelona will also take a hit in the shots department as neither Neymar or Suarez are averaging three shots per game; Messi was hitting close to five per game.

It might be an opportunity for either superstar to take control and be the main man for a short time, but if they continue playing as they have this season, Barcelona will see a big dip in offensive production.