Photo credit: AFP

There have been times this season when, for all their evident brilliance, Barcelona have been coasting through matches.

Arguably the high point of their campaign, the 6-1 win over Celta Vigo, saw Luis Enrique’s side produce some stunning football. Neymar, Lionel Messi and Luis Suarez tore the Galicians to shreds in the triumph, with a brash passed penalty routine epitomizing the swagger that was on show that day.

But even in that display, there were spells when the Blaugrana were a little ordinary mixed with bursts of enormous quality, with four of the six goals coming in a blistering 15-minute spell.

Indeed, even though they went on a record 39-game unbeaten run lately, which was ended with a 2-1 loss to Real Madrid in the Clasico, Barcelona have often been in cruise control, able to up the ante when needed due to the talent in their attacking ranks.

The last few contests have perhaps shown us why they have occasionally had to put the handbrake on. Barcelona have a small squad and as we reach the final knockings of the campaign, they’ve looked jaded in the Clasico, a 2-2 draw with Villarreal and a loss to Real Sociedad. And even though they rallied to a 2-1 win over Atletico Madrid in the first leg of the quarter-finals of the Champions League last week, ahead of the second segment of the tie, Diego Simeone will sense blood.

Barcelona head to the Vicente Calderon with a 2-1 lead, although possibly feeling as though they were let off the hook by the capital club. Fernando Torres nabbed a vital away goal before being given his marching orders, with Luis Suarez’s brace turning the game around in the second period.

It means Enrique’s men have something to cling on to when they head to one of European soccer’s most hostile venues, although for a side that’s looked a little leggy as of late, this opponent is probably the worst imaginable.

That’s because while Barca are enduring something of a slide, Atletico have found a brilliant balance to their play. Until Torres’ rashness cost them dear at the Camp Nou, they were superb, while either side of that encounter they enjoyed a 5-1 win over Real Betis and most recently, a 3-1 victory over Espanyol.

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Physically, Simeone’s players seem to have reached their peak too. Earlier this season they showcased a willingness to soak up pressure for long spells, looking to feed off scraps and keep clean sheets intact. But there’s been a clear emphasis lately to play with a shade more expansiveness and a greater willingness to exert themselves on opponents.

It’s that kind of suffocating style that Barcelona will have to counter on Wednesday evening. The two sides met at this stage a couple of seasons ago and while Atletico took a 1-1 draw back to the Calderon for the second leg, in the early stages of the home leg they pinned their illustrious visitors back with some high-intensity soccer, nicking a goal in the process.

With the insurance of an away goal, that’s surely what Simeone will profess to his players again. They’ll be extremely physical, squeeze the ball high up and offer a direct threat, with the likes of Antoine Griezmann and Yannick Ferreira Carrasco set to turn the Barcelona defense back to their own goal.

Of course, that could play into Barcelona’s hands, especially if the dangerous front three have spaces to exploit at the top end of the pitch.

Additionally, Enrique has proven himself to be something of an expert against Simeone’s sides, having beaten the Calderon club on every occasion he’s faced them as Barcelona boss. He’s steered his players to some vital wins too, most notably three points on the road to clinch the title last term and another win earlier in this season when Atletico were right on their tail at the top.

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But this match will be the biggest challenge Enrique has faced against this formidable foe. Atletico’s players, managers and supporters relish the underdog tag and while feasibly the fact that they need to show some attacking endeavor could free up space for Barca, they’re a club which is an image of its ferocious manager; they’ll be insatiable in their search for a vital goal.

For Barcelona fans, there’ll be a worry that after sleepwalking through a lot of games as of late, the champions will be unable to move up through the gears again with some critical contests to come. After all, having swept the board in La Liga, the Champions League and the Copa del Rey in 2014-15, the sky high levels of motivation may not be quite as prevalent this term.

For Atletico, they will be, especially after missing out on this title in the most heartbreaking of ways in 2013-14, when Sergio Ramos broke Rojiblancos hearts. This year they’re a team that are well equipped to prosper on the continent and provided they can keep their discipline in what’ll be a white hot atmosphere, the semi-finals beckon.