Kei Nishikori of Japan celebrates after defeating Novak Djokovic of Serbia
Kei Nishikori of Japan celebrates after defeating Novak Djokovic of Serbia in their semi-final match at the 2014 U.S. Open tennis tournament in New York, September 6, 2014. Reuters

Thanks to a pair of huge upsets in the semifinal round, Kei Nishikori of Japan and Marin Cilic of Croatia are the unlikely duo will contend for the 2014 US Open title on Monday in Flushing Meadows, New York.

Nishikori and Cilic brought down the big guns in Novak Djokovic and Roger Federer, respectively as both players aim to make history and grab their first-ever Grand Slam title in their respective careers.

How Nishikori, Cilic Reached the Final

Both Nishikori and Cilic lucked out in the early part of the tournament with victories via retirement. The Japanese was leading two sets to none when Pablo Andujar retired while the Croatian was in a similar scenario leading in the middle of the second set when Marcos Baghdatis left due to an injury.

Nishikori started getting the attention of the tennis world with his five-set classic over Milos Raonic when he came back down from two sets to one and then followed it up with yet another five-setter over Stanislas Wawrinka in the quarterfinals. He confirmed his serious Grand Slam contention with the semifinal win over top seed Novak Djokovic.

Cilic meanwhile was tested by Giles Simon in the fourth round and then easily dispatched Tomas Berdych (6th seed) and Roger Federer (2nd seed) in the quarterfinals and semifinals.

The Scores in the Previous Rounds

Nishikori defeated def. W. Odesnik (USA), 6-2, 6-4, 6-2 (first round); P. Andujar (Spain), 6-4, 6-1, retired (second round); def. L. Mayer (Argentina), 6-4, 6-2, 6-3 (third round); M. Raonic (Canada), 4-6, 7-6 (4), 6-7 (6), 7-5, 6-4 (fourth round); S. Wawrinka (Switzerland), 3-6, 7-5, 7-6 (7), 6-7 (5), 6-4 (quarterfinals); N. Djokovic (Serbia), 6-4, 1-6, 7-6 (4), 6-3 (semifinals)

Cilic defeated M. Baghdatis (Cyprus), 6-3, 3-1, retired (first round); I. Marchenko (Ukraine), 7-6 (2), 6-2, 6-4 (second round); K. Anderson (South Africa), 6-3, 3-6, 6-3, 6-4 (third round); G. Simon (France), 5-7, 7-6 (3), 6-4, 3-6, 6-3 (fourth round); T. Berdych (Czech Republic), 6-2, 6-4, 7-6 (4) (quarterfinals); R. Federer (Switzerland), 6-3, 6-4, 6-4 (semifinals)

Nishikori vs. Cilic Head-to-Head History (7 Matches, Nishikori leads Cilic, 5-2)

Nishikori def. Cilic, 6-1, 6-3 (Quarterfinals, 2014 Barcelona Open Banc Sabadell)
Nishikori def. Cilic, 6-4, 5-7, 6-2 (Quarterfinals, 2014 Brisbane International)
Nishikori def. Cilic, 6-4, 6-2 (Quarterfinals, 2013 U.S. National Indoor Tennis Championships)
Cilic def. Nishikori, 6-3, 6-4, 6-7 (3), 6-3 (Round of 32, 2012 US Open)
Nishikori def. Cilic, 4-6, 7-6 (0), 6-2 (Round of 32, 2011 Chennai Open)
Nishikori def. Cilic, 5-7, 7-6 (6), 3-6, 7-6 (3), 6-1 (Round of 64, 2010 US Open)
Cilic def. Nishikori, 6-2, 6-4 (Round of 128, ATP Masters Indian Wells)

For both Nishikori and Cilic, this is their first time in playing in a Grand Slam final and both knows that their respective victories over the top seeds Djokovic and Federer will be for naught if they can’t go all the way to the majors title.

Who will be the unlikely champion of the final tennis Grand Slam of the year?

Watch Nishikori vs. Cilic live streaming via these links: official website – 2014 US Open, Eurosport or the Tennis Channel.