Shkodran Mustafi says that Lionel Messi is the toughest opponent he has ever faced, such is his unpredictable genius.
Messi has been in astonishing form yet again this season, scoring 45 goals and providing 18 assists in just 54 appearances in all competitions.
He has yet to truly shine with Argentina on the grandest stage of them all, however, and will hope to inspire his team-mates to glory in Russia this summer.
Indeed, the Arsenal centre-back believes that Messi can pass any defence he comes up against, rating the 30-year-old as his best opponent.
"Lionel Messi was my hardest opponent," he told Bild.
"I played him three times with Valencia. You cannot predict him, he is small and very quick, changes his direction quite often.
"When he runs towards three opponents you can nearly be sure that he breaks through."
And the 26-year-old has weighed into the eternal debate comparing the two, insisting Messi has the edge.
"Ronaldo is more of a striker in the box," he added.
"Messi can also play good passes and make his team mates stronger. For me, he is the best player in the world."
Mustafi has also lauded the quality of the Premier League, and the unpredictability of the division, compared with Spain and Germany; Arsenal finished sixth, 12 points behind fourth-placed Liverpool.
"The Premier League is very exciting," he said.
"Every year, a different team can win the league and there is at least one top game every weekend. In Spain, there are only three teams. In Germany, Bayern play there own league. Besides that, everyone can beat everyone"