After consecutive premature and humiliating Champions League exits, Barcelona visit Porto on Wednesday aiming to make a statement in their trickiest group stage fixture.

Xavi Hernandez's side, five-time winners of the competition, have set their sights on returning to Europe's elite, with that goal informing their transfer strategy last summer.

President Joan Laporta sold off various parts of the club and a percentage of future television rights to fund a spending spree but the Catalans were left with egg on their faces after failing to make it past the group stage.

This summer the spending was far more restrained by necessity but Barcelona still managed to bring in Portuguese duo Joao Cancelo and Joao Felix on loan, as well as Manchester City midfielder Ilkay Gundogan to round out an impressive squad.

Xavi has a group of players which should be strong enough to battle with the continent's top sides, at least on paper.

The coach said Barcelona were concentrating on making it into the knockout rounds for the first time in three years, before setting any loftier goals.

After two consecutive tough group stage draws, this season Barcelona had more fortune.

They waltzed past Belgian champions Royal Antwerp with a 5-0 triumph in their opener but Xavi was quick to acknowledge it means little in terms of their overall chances, given they also thrashed Viktoria Plzen 5-1 in their first match last year.

"It's too soon (to say we can win it), last year we were in the same situation and it didn't go well, we have to be cautious," Xavi told reporters.

"We have to continue like this, we're on a good path... next up we have the most complicated match of the group, in Porto.

"We have the capacity, the confidence, but in the next game we have what I would say is the hardest game."

The clash at the Estadio Do Dragao against Porto, who did make it through the group in both of the last two seasons, will be a useful barometer of whether Barcelona are close to the level they want to be.

Veteran Porto defender Pepe, an old enemy of Barcelona with plenty of Clasico battle scars from his years at Real Madrid, is racing against time to be fit for the clash.

Milestone

The clash in the north of Portugal will be Xavi's 100th game as Barcelona's coach, during which time he has won La Liga and the Spanish Super Cup, but come up short in Europe.

Even dropping down to the Europa League did not prove fruitful in either of the last two seasons, with defeats by Frankfurt and Manchester United adding insult to injury.

"I have more experience and more peace of mind, I approach matches with more calm," he told Spanish newspaper Sport, discussing the milestone.

The Catalans are without injured trio Pedri, Frenkie de Jong and Raphinha, but 20-year-old midfielder Fermin Lopez has quickly established himself as a viable selection in midfield.

After last season’s transfer splurge on Robert Lewandowski, Jules Kounde, Raphinha and others, Barcelona now have to lean on their youth academy talents to supplement Xavi's options.

"It's a pleasure, it makes me proud (to have) players so young from here, who are performing and making the difference in games," said Xavi after Barcelona beat Sevilla last week.

"Normally the responsibility falls on those who are 24, 25... these players have to do it at 18, 16.

"It's the circumstances of how the club is too, we have to turn to the youth academy and it always delivers. They are doing things well there."