Jason Day currently the world's best, says Jordan Spieth

Jordan Spieth believes Jason Day is the man to beat at this week's Deutsche Bank Championship and feels the Australian is currently the world's best.

Day stormed to the top of the FedExCup standings with a dominant six-shot win at the Barclays last week, closing the gap on Spieth and Rory McIlroy at the top of the world rankings in the process.

Victory at Plainfield was Day's third win in his previous four starts, leaving Spieth, who lost top spot in the standings and his world No 1 status with a rare missed cut in opening play-off, convinced that the Australian is at the top of his game. 

"There's no doubt that Jason Day is the best player in the world right now," Spieth told a pre-tournament press conference. "Who would argue that after last week?

"He's playing the best of anybody right now and until somebody dethrones him he's still the man to beat. I look forward to the three of us and some to keep pushing each other.

"I think we are all focused on our own goals. As one, two and three in the world we are the three that have to beat each other right now in order to get to the top or remain at the top."

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The pair have been grouped together for the first two rounds alongside Bubba Watson in Boston, with live coverage of the featured group's opening round available via the Sky Sports iPad app. 

Day has earned plenty of plaudits in recent weeks with a series of tournament-winning displays, but the Australian still feels he hasn't done enough to earn the world No 1 spot. 

"I am playing good golf right now but with Rory coming back and Jordan, I can't say that I am," Day said. "It wouldn't feel right. The average is there for a reason. I have just got to keep playing well."

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