Arsenal goalkeeper Manuel Almunia says the key to English clubs' success in Europe is the depth in the Premier League.

Arsenal joined Manchester United, Liverpool and Chelsea in the next round, proving another year that European football is dominated by Premier League clubs.

"I'm not surprised," said the Spanish goalkeeper. "It just goes to prove that English football is at the top of Europe.

"In recent years we have seen that this has been the case and that the Premier League is the strongest league in the world.

"The difference is that in Spain or Italy you have three strong teams while in England you have five very competitive teams."

One thing Almunia hopes to avoid is an all-English quarter-final showdown for Arsenal.

"Any team would like to face the likes of FC Porto or Villarreal in the next round," he said. "No offence to these teams because they have merited being there.

"But I'd rather avoid an English side next. In any case, at this point of the season, any opponent will be difficult."