British number one Andy Murray has hailed clay-court specialist Rafael Nadal's forehand as "the best shot in tennis".
Speaking after he lost in straight sets to the world number two in the Hamburg Open third round, Murray said he believes his game is improving on his least-favourite surface.
The Scot has been working with former tennis pro Alex Corretja, who was renowned for his ability on clay, in recent weeks in a bid to improve his form ahead of the French Open later this month.
But he said he is still short of challenging players like Nadal, who are largely head and shoulders above their opponents on the ATP Tour.
"Nadal's forehand is the best shot in tennis," Murray told the BBC.
"When you go behind against him on clay it's very hard to get back."
Nadal was untroubled against Murray, breaking the world number 14 three times in the second set on his way to a 6-3 6-2 victory.
But rather than lamenting the reasons for his failure to compete with some of the top-ranked players, Murray said he is keen to keep working and keep improving in order to climb the rankings in the long term.
"I just want to concentrate right now on getting closer to the guys at the top," he continued.
"Whether or not I'll play as well on clay as on other surfaces, I don't really know.
"But my game is definitely getting better and that is one positive thing I can leave with."
© Adfero Ltd