If some sporting rises are rapid, Jacob Fearnley's progression has been played out in warp speed.

Little over a year ago, the 23-year-old Briton was unranked in the professional tennis world.

Six months ago, he was still a university student in the United States.

This week, Fearnley has moved into the world's top 100 on the ATP Tour - a significant landmark dangling the carrot of direct entry into the blue-riband Grand Slam events.

"Obviously, it is not what I expected," said the Scot, who moved to a career-high 98th on Thursday.

"It's come a little bit quicker than I, the rest of the people around me - and probably everyone - thought. I'm aware this isn't the norm."

Make no mistake, it is a remarkable rise.

Fearnley's climb to 98th in the world, from 646th at the start of this year, is the fourth biggest into the top 100 since 2000, according to ATP statistics.

Earlier this year, he graduated from Texas Christian University (TCU) with a degree in kinesiology - the study of human movement.

This is the point where Fearnley's ascent accelerated.

Moving to the US had long been on Fearnley's radar, and studying at TCU - where fellow Britons Cameron Norrie and Alastair Gray were alumni - seemed a logical choice.

"I was always a bit physically underdeveloped and school was a big thing - my parents wanted me to have something to fall back on if tennis didn't work," Fearnley said.

"I also didn't feel ready mentally to play tennis. I wanted five years to develop my game, develop as a person, socialise and meet new people."

When Fearnley arrived at TCU, coaching staff at the 'Frogs' saw a shy 18-year-old initially held back on the court by self-doubt.

The nature of US college tennis - all noise, trash talking and team bonding - is not for the faint-hearted.

"College tennis is a very emotional form of tennis. There is a lot more energy from the players and other teams," Devin Bowen, assistant coach of men's tennis at TCU, told BBC Sport.

"It was a great environment for Jake because it tested him. It is a good opportunity to grow up, build character and find out who you are.

"It is exciting and a lot of fun. But it can also really be brutal."

Fearnley always had "something special" but needed time to trust his ability, according to former ATP doubles player Bowen.

Eventually he did.

A five-year spell in Fort Worth brought a host of individual and team accolades, culminating in TCU's first national men's tennis title.

"His mind used to get super overly-dramatic," Bowen said.

"Five minutes before the match he'd say 'I can't find the grip on my forehand. It's all falling apart'.

"I'd say 'you'll settle in, your mind is playing tricks on you'.

"Now he has experience, and a little wisdom, to know it is what the mind does before big matches."

Fearnley's love of tennis came through mum Samantha and his grandad.

Born in English cathedral city Worcester, he moved to Edinburgh aged two and grew up in the Scottish capital.

From knockarounds in the backyard with a bat and ball aged two, he progressed to honing his skills on courts near his home in Dalkeith.

A move to Merchiston, Scotland's only all-boys independent boarding school which boasts a tennis academy, came aged 11.

By that time, he was already rubbing shoulders with the cream of Britain's next crop of youngsters.

One of them was Jack Draper.

The British number one, ranked 20th in the world after reaching last month's US Open semi-finals, is five months younger than Fearnley.

The pair go way back. Last week Draper shared a slightly blurry photo of them as starry-eyed kids on Centre Court.

Draper's path through the junior ranks was more successful, however, culminating in an appearance in the Wimbledon boys' final in 2018.

While there were notable wins against Grand Slam champions Jannik Sinner and Carlos Alcaraz in his junior days, Fearnley's teenage development was a slow-burner.

"People around me - my coaches and my parents - were saying that everyone has their own path," Fearnley, who is coached by former TCU team-mate Juan Martin, said.

"I was very patient. I was not comparing myself to anyone.

"Jack [Draper] was simply a lot better than me and that is totally fine.

"I don't think comparing myself to someone like him would have been beneficial for my tennis."

Within weeks of leaving TCU, Fearnley returned to Britain for the grass-court season.

Winning an ATP Challenger title in Nottingham was the first step into the spotlight back home.

The second-tier success led to a Wimbledon wildcard and, ultimately, a contest against 24-time major champion Novak Djokovic on Centre Court which provided invaluable experience.

After Wimbledon, Fearnley switched back to hard courts and has rattled off 20 wins in his past 21 Challenger matches.

The hat-trick of titles the run has yielded - one in the US and two in France - have propelled him into the top 100.

No player comes close to matching the 547 places he has climbed this season.

Fearnley, naturally, hopes making the top 100 will not be the end of his rise.

He still has played only two tour-level events - Wimbledon and Eastbourne this year.

Stepping up to the main ATP Tour, where consistency and clarity of thought sets the best apart, will be a real test.

Fearnley describes himself as an "aggressive counter-puncher" whose strength lies in his movement and getting "a lot of balls" in the court.

He is planning to play qualifying in Stockholm, Basel and Vienna before the season ends.

"The levels get higher, everyone's doing things slightly better so it's just adjusting my game to the demands of the sport," he said.

"I'll see how my game fares in the ATP events.

"No matter what the outcome, I'll learn a lot from those experiences and use that to improve my game."