I feel Nishikori needs to build up some muscle to break into the Top-10. With the game getting more physical, (we saw in the Australian Open final) players without any weapon are brushed aside easily by the higher ranked players. Nishikori showed his caliber when he Jo-WIlfried Tsonga, but needs to develop one stroke to hurt his opponent. He is no doubt very fit! But then he can not keep running the balls down and also hit winners at the same time. Nishikori is a future Top 10, but breaking into it soon looks highly unlikely.