The unseeded Eala started her North American hard-court campaign with a come-from-behind win over reigning Olympic champion and former world No 4 Zheng Qinwen as she lost the opening set before winning in three.
She followed it up with a straight set wins over seventh seed and defending champion Leylah Fernandez and second seed and former world No 3 Elina Svitolina to set up a match against Osaka.
And now for the third match in a row, she won without dropping a set as she secured a 6-4, 6-2 win over the four-time Grand Slam finalist.
After trading breaks early in the opening set, Eala claimed the crucial break in game nine and then took the momentum into the second set, breaking in the opening match and again in game eight before wrapping it up on her third match point on serve.
“Going into this tournament, I looked at the list, and it was jam-packed,” the 21-year-old said.
“It was big player after big player after big player. So to be in the final really means a lot to me.”
And now she can add Osaka to the list of “big players” she has beaten on her run in DC.
“She definitely has an aura and she definitely has power,” she said of Osaka.
“I remember watching her finals in the Australian Open and US Open, so really a great experience to share the court with her.
“I’m really happy I was able to produce that level against her. I’m super proud of my performance. I played really well and I had a great mentality and I stayed locked in until the end.”
