Rafael Nadal hopes his hard work will pay off in a rewarding end of the season, starting this week in Cincinnati and extending into the U.S. Open.

The eighth-ranked Spaniard comes into the Western & Southern Open after losing to No. 4 Kei Nishikori in the quarterfinals of the hard-court Rogers Cup in Montreal.

Nadal said Monday that "this is an important week for me."

He adds: "I played OK in Montreal, but every week is a different test — a different story. I'm working more than ever to change the dynamic."

That would mean avoiding the injuries that have plagued him over the past few years, including 2014, when he was unable to defend the 2013 championships he won in Cincinnati and at the U.S. Open.

Nadal says: "The last part of the season is important. I want to finish feeling better than when I started."