Germany centre-back Arne Friedrich is not under-estimating the threat of Wayne Rooney despite the England striker misfiring so far this World Cup.
The Manchester United ace went into the tournament as one of the favourites to win the Golden Boot after scoring 26 goals in 32 Premier League games last season.
But the 24-year-old has failed to find the net so far, spurning several gilt-edged chances in England's Group C campaign.
But Friedrich is not under-estimating a player of Rooney's class as the old rivals prepare for Sunday's last 16 clash.
The 31-year-old, who will be at the heart of the German defence, said: "Wayne Rooney has incredible qualities, he has proved that year after year.
"He might have been a bit off form here, but he is a player who can come into his own very quickly.
"We will be on our guard here against someone of his calibre and we know if he gets half a chance, he will take it."
The Germany squad were relatively inexperienced going into this tournament but Friedrich says they benefited from their nail-biting 1-0 win over Ghana on Wednesday to book their date with England.
He said: "We have certainly learned from the match, it was important for everyone to go through that pressure and experience it.
"We had very little to win and a lot to lose as everyone back home thought we would reach the round of 16.
"England are favourites, but the Ghana game has made us mentally stronger which will help us for the next game."