Rafael Nadal is the World No. 1 player as of Monday. However, the Spaniard didn't ascend back to the top of the ATP's rankings thanks to titles on the hard-court surface. Nadal's bread and butter have been the clay-court surface over the years, and he is back to No. 1 mainly for what he did in the spring of this season.

The Twitter account for ATP Media Info indirectly referenced this a few days ago. That account tweeted a very interesting statistic for those that think Nadal will be a major factor at the upcoming US Open. The Spaniard may, in fact, be overrated heading into Flushing Meadows.

"Next week's World No. 1 Rafael Nadal," the ATP tweeted on Friday, "has played 34 hard-court tournaments since the last title on the surface (2014 Doha: Nadal d. Gael Monfils)." The title mentioned in the tweet wasn't in a big tournament, and maybe it's worth mentioning that 2014 Doha was played in early 2014. In short, you have to go back 3.5 years to find a time when Nadal won a hardcourt event, and that event was a low-tiered one at that. If you want to talk about Nadal winning an event on cement that was well contested, then you'd be talking about the US Open in 2013. That's four years to the tournament that Nadal has gone without winning a significant title on the hardcourts.

Looking back at 2013's title

Of course, heading into the 2013 US Open, the Spaniard had all kinds of amazing form going his way.

He had won both Canada and Cincinnati that season immediately before the US Open. The Spaniard had also won Indian Wells in 2013 as he enjoyed a ten-title season. But the fact that it's four years since that golden time in his hard-court career discredits the notion that he is going to win the US Open this year. Let's not forget about Fabio Fognini and Lucas Pouille taking Nadal out of the US Open the last two years.

Each match was well contested, but neither Fognini nor Pouille was a factor for the title. In short, it hasn't taken a title threat to take Nadal out of the US Open draw since his last title run at Flushing Meadows (he didn't play in the 2014 tournament).

With defending champion Stan Wawrinka out with injury, multi-time champion Novak Djokovic out with injury, and Andy Murray entering the US Open without a hardcourt match played since losing to Vasek Pospisil way back in Indian Wells five months ago the conditions seem to favor either Roger Federer or an upstart player.

Federer has made some strange comments of late, and he didn't look good in the Montreal final. On that note, Alexander Zverev and a resurgent Grigor Dimitrov could reach new Grand Slam heights. Nick Kyrgios can't be ignored either, but he's one to watch for bad news following his efforts in Cincinnati given his history.

Hard-court history very important

Nadal's die-hard attitude toward every match makes him dangerous no matter what. But 34 tournaments in a row that he has gone out on cement since the last time title on the surface? Denis Shapovalov and Kyrgios did numbers on the Spaniard in recent weeks? If Nadal is the second favorite behind Federer on your US Open list, then it just attests to how wide open Flushing Meadows is this season. The tournament might be 15 players deep in contenders, including Nadal but not stressing him.