Diego Reyes, Diego Lopez key to Espanyol's stingy defence vs Barcelona

Diego Reyes emerges slightly late from the dressing room at Espanyol's Ciutat Esportiva Dani Jarque -- he can be forgiven, he was watching the final minutes of his former side Club America's FIFA Club World Cup semifinal defeat to Real Madrid -- but being late is not something he's made a habit of this season.

Since making his first start for his new club at the beginning of October, he's committed just six fouls and he's yet to pick up a booking. What's more impressive is that since Reyes came into the team nine games ago, Quique Sanchez Flores' side have not tasted defeat. It's a run which has seen them keep seven clean sheets and leak just four goals, as they've moved into the top half of the table. There's no meaner defence in Spain at the moment -- in that same time period, Madrid have conceded eight, Barcelona nine and Atletico Madrid 12.

Nicknamed El Flaco, Reyes doesn't immediately conjure up images of the traditional centre-back when you see him. Despite being tall, he is, as his epithet suggests, skinny. And despite being 24, he could still be mistook for a teenager. He's mature, though. Since leaving America in 2013 for Porto, he's been living on his own, with his family and his girlfriend still in Mexico, but loan spells at first Real Sociedad and now Espanyol have helped him grow up.

Reyes' professional debut in his homeland came as a much-hyped teenager in midfield, but it's in defence where he currently forms a formidable partnership with another converted midfielder, David Lopez. On Sunday, they will be tasked with keeping yet another clean sheet, albeit with a twist: this time it's Lionel Messi, Luis Suarez and Neymar they'll be up against when they make the short trip across the city for the Catalan derby.

"We hope we can keep them out," Reyes tells ESPN FC from Espanyol's Barcelona training base. Most people hope they can, of course, but few actually can. The Mexican defender is among those few. He was part of the Real Sociedad side which beat Barca 1-0 in April. Now he's looking forward to the challenge of doing it again.

"Every game is different," he continues. "Last season Suarez didn't play that game against La Real, but we know what [the MSN] represent. They're great forwards with huge talent, but we also have our own weapons to put up a fight and try to win. It's not about being afraid of [the MSN]. Why would you be? They're people like all of us. It's an added motivation, but they're just human beings like you and me.

"There aren't any tricks [to stopping them]. It's just a case of doing what we've been doing until now. There's a reason we've kept so many clean sheets. We all know the importance of the game. It's my first derby, I don't know a lot about it but people have told me it's a passionate game. I'm aware of the size of it for the club: people tell me on the street. They don't stop reminding me!"

One of the weapons Reyes refers to is Espanyol's defence. During their win against Sporting Gijon last time out, goalkeeper Diego Lopez broke a club record as he passed the 550-minute mark without conceding in La Liga. A stoppage time free kick from Duje Cop eventually brought the run to an end at 586 -- and denied Barca the potential pleasure of ending it themselves.

Reyes wouldn't describe the Pericos as a defensive team, however. A recent Chinese take over at the club led to a summer overhaul of the squad and he feels it's only natural that it took some time for things to click. Now, he suggests, we are seeing the best of the team managed by former Watford coach Flores, who himself only arrived at Cornella-El Prat this year.

"It's just a case of being more adapted to what the manager asks of us now," he responds when asked about the contrast between Espanyol's current form with how they began the campaign. "We have 11 new players and we didn't really know each other. Now we're improving because we're finding out more about each other, how we like to play, our movements and what's needed on the pitch to help [teammates]. That helps.

"We're all running and fighting for the ball, which is important. [Defenders] need the help of the forwards to defend and to attack. It's not a case of four defenders and a goalkeeper [keeping clean sheets], it's the squad.

"[Flores] is definitely not a defensive coach (...) but he's a coach that likes his teams to be prepared at the back. He knows that everything starts from keeping clean sheets and from that point we can go on and achieve good results because further forward we have lethal players in attack who can change a game. He's a demanding manager, he knows how he wants to play and he demands a lot from you in training and in games."

And what about the future? Reyes, after all, has only been borrowed by Espanyol, who do have an option to buy him next summer. It's something he would like, he hints, but he insists his sole focus right now is on beating Barca.

"Of course I would like to stay [at Espanyol]," he says. "I'm very happy here, but it's not my decision. I belong to a great club in Porto, so we will have to sit down next summer and see what happens. To be honest I'm not thinking long term at all. Those decisions aren't to do with me and I am just focused on playing well against Barcelona and continuing to pick up points.

"We won't change our style to play them, why would we? That's what's got us to where we are at the moment. Working together as a team and everyone wanting the same thing is the only way to take us far. We're only worried about ourselves. I think I'm going to enjoy it a lot. I'm going to be doing what I most like doing: playing football."