Dele Alli turns 20: A quartet of other England kids once tipped for stardom

Amid a breakthrough season that's vaulted the prodigious talent from the near-obscurity of Milton Keynes Dons to starring for club and country, Tottenham stud Dele Alli celebrated his 20th birthday on Monday.

Like many before him, Alli has become the favourite of pundits who are quick to anoint the versatile midfielder as the next best English talent. To Alli's credit, his performances for the title-chasing Spurs and England this year have been immense.

As a warning of sorts, here's a look at four English players who were once hailed as teenage talents, only to fizzle out and leave football with barely a notice:

Francis Jeffers

Francis "Fox in Box" Jeffers was tipped to be the latest in a long line of Arsenal stars when he signed for the Gunners in 2001 from Everton. Joint all-time highest scorer for the England Under-21's with 13 goals in 16 appearances, the Liverpool-born striker had the assets of a future star.

With one England senior-team cap paired with a goal against Australia, Jeffers was destined to be a world-class footballer. His tenure at Highbury was hampered by injury, prompting a loan back to Everton in 2003. Like a football flying down a hill and out of sight, Jeffers' career followed a similar trajectory. Spells with Charlton, Blackburn, and Sheffield Wednesday preceded less-heralded moves to Australia, Malta, and Accrington Stanley, where he retired in 2013.

Billy Kenny

One of the highest-rated young English players of the 1990s, Billy Kenny appeared to have all the tools to be a footballing star. Tough and tireless with an eye for a pass, Kenny launched a once-promising career at 19 with both Everton and England's Under-21 side.

Nicknamed the "Goodison Gazza" by former Three Lions standout Peter Beardsley, Kenny was pegged to be England's next superstar, only for a bout of shin splints to sideline the Merseyside-born midfielder for six months. Clinically depressed, Kenny became addicted to cocaine and alcohol, was sacked by Everton a year later, then again by Oldham Athletic prior to his retirement at age 21.

Jermaine Pennant

Like Jeffers, Jermaine Pennant signed with Arsenal as a highly regarded teenager. Blessed with pace and a quality final ball, Pennant thrived on the wing with Notts County's academy before the big-city move for a then-record fee for a trainee of £2 million.

Pennant made his debut for a star-studded Arsenal side aged 16 years and 319 days against Middlesbrough in the League Cup, making him the club's youngest ever first-team player. That record has since been surpassed by Cesc Fabregas and Jack Wilshere.

The Nottingham-born winger had to wait another two-and-a-half years to make his Premier League debut. A mix of disciplinary problems and trouble acclimating prompted loan spells with Watford, Leeds, and Birmingham City. A term with Stoke City from 2011-14 was Pennant's last chance at top-flight stardom, and he failed. He has since moved on to India, Wigan Athletic, and Singapore.

Lee Sharpe

A member of Manchester Untied's famed Class of '92, midfielder Lee Sharpe was pegged to reach the pinnacle of top-flight football alongside academy mates Ryan Giggs, David Beckham, Paul Scholes, Nicky Butt, and the Neville brothers.

Aged 17, Sharpe made his first-team debut in September 1988 against West Ham. Two years later, he earned his first England cap and the honour of winning the PFA Young Player of the Year award. At 19, the talented winger was a few rungs from the top of the game. At 31, he was without club, after making a pittance during a dismal four-game spell with Exeter City.

A spell in Iceland as well as with non-league Yorkshire side followed, as a career of rife with promise ran out of gas far from its destination.