Emil Ruusuvuori is champion in Chengdu.

The Finn prevailed 3-6 6-1 7-6(4) in a pulsating final against Chinese prodigy and world junior No. 1 Yibing Wu to hold aloft the ITF Junior Masters trophy.

"It's amazing. It's hard to find words for how happy I feel right now," said the elated 18-year-old, who will surge into the top 10 in the junior rankings after his finest triumph yet - but already has an eye on the senior tour.

"It can be my springboard for the pro circuit," said Ruusuvuoiri. "It's a huge challenge and that's going to be such fun."

Top seed Wu was looking to bring down the curtain on his junior career with silverware on home soil and held a favourable 2-0 head-to-head over his opponent as the duo entered centre court.

Wu won their enthralling encounter en route to the US Open title and also navigated past the eighth seed in straight sets during the round robin stage in Chengdu. However, Ruusuvuori has defied his current ranking of world No. 15 all week, with a fearless brand of all-court tennis.

It was the top seed who sparked the final into a life. A cross court forehand launched into the corner brushing the tramline, which provided a warning sign for the towering Finn.

Wu is a keen basketball fan and channelled his NBA knowledge to snatch away the initiative. At 3-2 the local favourite latched onto a Ruusuvuori smash and in mid-flight clattered a forehand passing shot in a slam dunk pose. The ardent home support leapt up in applause as Wu chalked up 4-2 on the scoreboard, then sealing the set with an ace.

The momentum was well and truly in Wu's favour and a backhand winner on the stretch offered up a trio of break chances to start the second set.

"Wu was playing so well in the first set, so I knew I had to change something," revealed Ruusuvuori. "I slowed the play down, changed the shape of all my shots to make it awkward for him."

Ruusuvuori sparked into contention with eight successive points. That imposing run earned a 2-0 lead and within minutes a rapid set was falling away from Wu, when his rejuvenated opponent looped over a sumptuous lob to race 4-1 ahead.

A hold to love sent the absorbing finale into a decider and once again Wu seized control. He roared in delight as a barrage of groundstrokes sent the world No. 1 onto the cusp of holding the trophy at 4-1.

Ruusuvuori was far from finished. "He found great variety and was brave when I was up in the third set. A match like this can turn in one point and I missed a few easy balls," explained Wu. "I tried to stay aggressive and I felt so much pressure, but his defence was incredible."

The Finn had dissolved Wu's lead and the fans, players, coaches and event staff all vied for the finest vantage point to witness this miraculous match reach its conclusion.

A tiebreak was required to offer up the trophy. It followed a familiar pattern, with Wu firing an ace and a blistering backhand to inch 2-0 in front. It was also accustomed that Ruusuvuori would produce inspired, instinctive tennis when he was behind on the scoreboard. He canvassed the net and arrowed shots past Wu to storm to the prestigious title.

"I have no idea how I won that, the tiebreak was so tight. I had to stay in the moment and focus on my game," added the Finn, who beamed with pride as the lowest-ranked player prior to the tournament. "It's for sure the best win of my Junior career."

Wu is determined to learn from his Chengdu championships, but paid credit to his opponent.

"I'm very happy for Emil," said a gracious Wu. "It was a really great match for both of us. It could turn into a real rivalry."

Wu was delighted to see his Junior career culminate on home soil and is optimistic ahead of the challenges posed as a professional in 2018.

"I feel very thankful, this has been a really enjoyable tournament. I hope I can have a lot of successful tournaments like this next year," added the Chinese leading light.

"I'll aim to reach the qualifying rounds of the Grand Slams in 2018, that is my priority, but it is more about improving my level rather than earning ranking points."

Second seed Axel Geller picked up the bronze medal in his final junior tournament.

The 18-year-old will now work on his fledging tennis career whilst studying at Stanford University in the United States.

Geller was defeated by his compatriot Sebastian Baez in two tiebreak sets during the round robin event, but gained revenge in a brutal two-hour 6-1 6-7(9) 6-4 battle.

"I'm happy that I could redeem myself as I lost to him earlier this week. I felt much better today, I should have won in straight sets as I had two match points but he fought back well," said the world No. 2. "I wanted to be in the final but I'm happy as I didn't want to finish my Juniors with a loss.

"It's been a great experience here, playing matches at a high level as a means to becoming a pro."

Meanwhile, Marko Miladinovic finished his ITF Junior Masters on a high with two consecutive wins, cruising past Jurij Rodionov 6-3 6-2.

"I feel great because I lost against Rodionov in the group. It was also 6-3 for me in the first set but in that match I started to be nervous and I think that was the reason I lost. Today I was losing 2-0 in the second set and was also nervous but I tried to be positive," reflected the ambitious Serbian.

"The biggest difference between the first three days and last two days was because I stayed positive. I wanted to play and feel good because I'm playing at the Junior Masters.

"This is a very big tournament and I look to all these players to build my confidence, because next year I can be No. 1."