John Isner will face Kei Nishikori in the final of the Citi Open after a narrow victory in Saturday’s second semi-final.
Nishikori had already booked his place in the final with a 3-6, 6-1, 6-4 win over Marin Cilic when Isner took to court against Steve Johnson.
And the American went on to set up his second match against the Japanese by claiming a 6-3, 3-6, 7-6(11-9) victory in 118 minutes.
"It was incredible. With this atmosphere, playing under the lights, perfect conditions with no wind, it wasn't hot and the crowd was into it,” Isner told the ATP website.
"I've been in this situation before (in the tie-break). I tried to take care of my serve and put the pressure on him.
“I didn't do it that well because I was playing from behind for the most part, but I didn't get too rattled and believed in myself.
“I had the wins coming into this match and it goes a long way. It's not a tangible thing, but confidence is huge."
Isner, who won his only other match against Nishikori, has played in two previous Citi Open finals but is yet to win the title.
He finished as runner-up in 2007 after losing to Andy Roddick and in 2013 after losing to Juan Martin de Potro.
The match will be Isner's second consecutive final on the ATP World Tour after he defeated Marco Baghdatis to win the BB&T Atlanta Open last week.