Per Mertesacker credits former Liverpool star as his most difficult opponent

Fernando Torres may no longer be at the peak of his powers, but he gave Per Mertesacker a torrid time a few years ago.

Arsenal centre-back Per Mertesacker has faced some of the most formidable forwards in Europe during his time at the Emirates Stadium.

The Gunners have faced up to the likes of Bayern Munich, Borussia Dortmund and Barcelona in recent years in the Champions League, who have contained some of the world's most illustrious forwards like Lionel Messi and Robert Lewandowski - whilst the Premier League has had plenty of top attacking talent for the German to pit his wits against.

But it isn't either of those players mentioned, nor is it any of the illustrious names such as Diego Costa, Luis Suarez or Wayne Rooney who have had success against Arsenal, but Fernando Torres.

To some it may be a little surprising given the Spaniard's form of late, which has seen him move on loan to AC Milan from Chelsea, but there was a time when Torres was one of the most feared strikers in Europe.

Mertesacker explained to "If I think back to the [UEFA EURO 2008] final against Spain, it was Fernando Torres. I would name him for that time. But you face a new challenge every week in the Premier League, playing against strong opponents, and that's what you have to prepare for. But I enjoy that."

Torres scored the winning goal in the Euro 2008 final against Germany in Vienna which sparked an era of dominance for the Spanish national side, and the Premier League saw him at the peak of his powers during his time at Liverpool.

Ever since he made the move to Chelsea for £50 million in January 2011, he has failed to recapture his best form which led to him falling down the pecking order and seeking his loan move to Serie A. 

In a way, Mertesacker's comments are another reminder of just how talented a footballer Torres was, and how sad his decline in form became in the past four years.

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