Wimbledon runner-up Nick Kyrgios won his seventh ATP title and first in three years by defeating Japan's Yoshihito Nishioka in Sunday's men's final at the ATP and WTA Washington Open.

The 27-year-old Australian downed 96th-ranked left-hander Nishioka 6-4, 6-3 for his first ATP title since capturing the 2019 Washington crown.

"It's emotional for me to be back here again and claim another title," Kyrgios said.

Kyrgios, who lost to Novak Djokovic last month in his first Grand Slam final, made back-to-back tour-level finals for the first time in his career and didn't allow a service break all week.

"It's just very emotional for me to see where I was at last year to now. It's just an incredible transformation," Kyrgios said. "I've been in some really dark places.

"There are so many people who have helped me get there but myself, I've shown some serious strength to just continue and just persevere and get through all those times and be able to still perform and win tournaments like this one."

World number 63 Kyrgios fired 12 aces and 32 winners against four double faults and 20 unforced errors while taking 22 of 25 first-serve points to defeat Nishioka in 81 minutes.

"I came out with great energy," Kyrgios said. "I knew I had experience on my side. I'm really happy with myself."

Kyrgios improved to 4-0 against Nishioka, the most recent prior win coming in the third round of his 2019 Washington title run.

In the women's final, Liudmila Samsonova won her second career WTA title by beating Estonia's Kaia Kanepi 4-6, 6-3, 6-3. Her first title came at last year's German Open on Berlin grass.

"It's like a dream," Samsonova said. "It's unbelievable."

Kyrgios became the first man to sweep singles and doubles titles in the event's 53-year history -- a feat he called "super special" -- by joining American Jack Sock to beat Croatian Ivan Dodig and American Austin Krajicek 7-5, 6-4 in the final.

Nishioka netted a backhand to surrender a break in the opening game and Kyrgios denied the Asian southpaw's lone break chance with a backhand winner in the sixth game, holding out to claim the first set with his seventh ace.

Kyrgios broke in the first game of the second set when Nishioka sent a forehand long and again in the final game when Nishioka netted a backhand on the Aussie's third match point.

Nishioka, who captured his only ATP crown in 2018 at Shenzhen, hadn't won a tour-level match since March until this week, when he upset eighth-ranked Andrey Rublev in the semi-finals. He will jump to 54th in Monday's world rankings, six off his career best.

"At the beginning of the year I had a nightmare," Nishioka said. "I thought if I can't make the top 50 again I will retire. Now I think maybe I can play a few more years."

Kyrgios will leap to 37th in the world rankings. He would have been 15th had world ranking points been awarded at Wimbledon.

Kanepi drought extended

World number 60 Samsonova fired 10 aces and 27 winners to beat Kanepi. The 23-year-old Russian came off a six-week layoff after Russian and Belarus players were not allowed at Wimbledon due to the invasion of Ukraine.

"I think we are all very angry about the situation. It was a really tough month," said Samsonova, who only got her US visa two weeks ago.

Kanepi, ranked 37th at age 37, was foiled in her bid to end a nine-year WTA title drought. She last won a WTA crown at the 2013 Brussels Open.

"Overall the week was very good," Kanepi said. "She served better than me and maybe that was the key."

Samsonova dispatched three of the top six seeds, ousting reigning US Open champion Emma Raducanu, fifth seed Elise Mertens and sixth seed Kanepi.