AMERICAN young gun Ben Shelton continues to defy the odds in his maiden Australian Open, reaching the quarterfinals of the event after securing an incredible five-set win against close friend J.J. Wolf. In a match that lasted three hours and 47 minutes, and feature three tiebreakers across five sets, Shelton booked his place in the last eight.

In another outstanding performance from the big-serving 20-year-old, Shelton won 6-7 6-2 6-7 7-6 6-2 to come from two sets to one down and set up another all-American clash in the quarterfinals. Shelton has been quite the revelation at Melbourne Park, winning through to the final eight in what was his first ever trip overseas.

“It’s been a dream so far, really like playing out here in John Cain so thanks everyone who came out the last two matches it’s been amazing,” Shelton said post-match. “You guys are the best.”

The youngster admitted it was tough playing a close friend, knowing that the it would be a “battle” and far from easy. Shelton served up 23 aces for only one double fault, winning 82 and 69 per cent of his first and second serve points off a 68 per cent clip, including a ridiculous first serve average speed of 196 kmh.

“I’ve known JJ for a while and he’s a great guy, I think another part of it is conserving energy today,” Shelton said. ‘I knew it was going to be a battle, and I knew I couldn’t come out here and be all amped up for all four hours or I wouldn’t make it. I kind of paced myself emotionally and I was able to bring out my best tennis at the end of the match.”

Shelton thanked his coaching and fitness team for working on his endurance and getting to this point. He conceded six months ago he would not have been able to run out a four-hour match, but played the best tennis of the day in the final few games.

“It was definitely a gruelling match, there’s a lot of swings throughout the match,” Shelton said. “It was going to him, and then me, and then him and then me. I really focused on in the fifth set being energetic, trusting my fitness, just hustling, being courageous and I thought I did a really good job competing at the highest level in the fifth set.”

Entering the tournament at a career-high 89th in the world, Shelton’s run to the quarterfinals has seen him rise 46 places into 43rd. He takes on another compatriot in Tommy Paul, with the world number 28 rising seven spots to match his equal career-high ranking. If he can overcome Paul, he will move up to 33rd in the world and potentially play nine-time Australian Open winner, Novak Djokovic.

“It’s going to be a war,” Shelton said. “Quarterfinals of a Grand Slam I’m ready to go to battle, I’m happy accepting the challenge and let’s get after it again, come on.”