January, Jamal Blackman confides, is a time when the messages flash up with extra frequency in the WhatsApp group for Chelsea’s 36 loan players. “Around the transfer window, people are buzzing because they are moving, they are going here and there,” explains the goalkeeper, currently on loan at Wycombe Wanderers. “When you are away from it, you don’t know what is going on, but you hear it in the WhatsApp group so it is nice to be connected.”

There is another reason, though, why his phone has been beeping more than usual in the past couple of weeks. After all, Saturday brings a trip for the 23-year-old to White Hart Lane for Wycombe’s FA Cup fourth-round tie with Tottenham Hotspur – and the WhatsApp group have not been slow in letting Blackman know what they want.

“Everyone is talking about penalties,” grins Blackman, settling his giant frame into a seat in the games room at Wycombe’s training ground. “They’re saying, ‘If Tottenham get a penalty, Jamal has got to save it!’”

There have even been tongue-in-cheek requests to “just take them down” to make sure he gets the chance to show what he can do from 12 yards – a measure of the 6ft 6in goalkeeper’s reputation as something of a spot-kick specialist. There have been four saved penalties since his arrival at Wycombe – one of them in a shoot-out against Blackpool during the club’s run to the Checkatrade Trophy semi-finals.

Blackman could certainly be given a wry smile if he did end up facing a Spurs spot-kick – albeit less for his recent prowess than for what happened on the only previous occasion he has stepped out in a first-team game at one of English football’s grand arenas. It was his first, and only, senior appearance on loan at Middlesbrough, and he ended up facing 15 penalties in front of the Kop at Anfield.

That League Cup tie in September 2014 produced a record-equalling shoot-out, which Liverpool eventually won 14-13, and Blackman recalls: “It was a weird experience, good and bad. The longest penalty shoot-out. I saved a penalty from Raheem Sterling, which was good for me. And I scored a penalty.”

Blackman with Chelsea's Thibaut Courtois (Getty)

Blackman's Chelsea finishing school: “I grew up having Frank Lampard take penalties at me, and Didier Drogba, John Terry, Ashley Cole too. You just learn different ways people take penalties so I’ve had loads of experience. Drogba and David Luiz together doing free-kicks was also fun – the ball would go anywhere and everywhere. "I first went into the first team when I was sixteen and did a shooting drill with Alex and he ran up and smacked it as hard as possible. I remember trying to put my hands there but I then realised, ‘No, just get out of the way!'”

A few months before, Blackman had stopped two penalties to win Chelsea U21s a semi-final shoot-out against Manchester City en route to the 2014 Premier League trophy. That night at Anfield, though, was football on another level. “It was every emotion you could think of.”

And for a player who had grown up at Chelsea, after signing for the U13s a decade ago, and who had won the FA Youth Cup and sat on the bench in Champions League matches, it was a first taste of the one thing Stamford Bridge has not been able to bring him – proper men’s football.

For this reason he is so enjoying the experience at Wycombe, where he has played a significant role in a 16-match unbeaten run for Gareth Ainsworth’s League Two promotion-chasers. The sight of a mattress resting against a wall in the games room at the training ground underlines we are far from the comforts of Chelsea’s shiny Cobham HQ but in Buckinghamshire, where he has just extended his loan till the season’s end, he is learning important lessons.

Ainsworth speaks of Blackman’s growing confidence in using his size to dominate his penalty box. The player himself is enjoying the relentless, prove-yourself-twice-a-week rhythm of lower-league football.

Wycombe Wanderer's manager Gareth Ainsworth ahead of Saturday's game (Getty)

Blackman, capped by England at U16, U17 and U19 levels, says: “I’ve been in and around the first team with Chelsea so much but I wanted to get out and say, ‘Look, I can play in men’s football, it’s no problem'. You need to adapt to having a Saturday game and then a Tuesday game, having a routine where you’re in, you need to watch what you’re eating and watch what you’re doing outside of football, and making sure you maintain that.”

If he cuts a giant figure in Wycombe’s goal, they have up front the even more formidable figure of Adebayo ‘The Beast’ Akinfewa. Blackman has not, he clarifies, tried clearing him out in training – “We try to stay away from each other!” – and the 16-stone striker’s presence has entailed a different approach to ball distribution than he had known first at Chelsea and then during a loan spell at Östersund in Sweden last spring.

“From the academy you learn to play it out, to pass it out from the back and through the team. I was lucky enough to go to Sweden where it was the same kind of football – pass it out. My first game here I got the ball and looked to play out and everyone’s like, ‘No, you’re going straight to Bayo’ and he has just stood there and chested it’.”

Wycombe Wanderers players in training (Getty)

It is easy to be cynical about Chelsea’s hoarding of young players who have no apparent chance of ever playing for their first team. Blackman, first spotted by Chelsea when playing for a club in Croydon run by ex-Wimbledon and Charlton Athletic midfielder Jason Euell, sees it differently. His contact with the club is not just via the WhatsApp group. He receives a weekly visit from Christophe Lollichon, a goalkeeping coach from the London club.

Indeed once our interview is over, Blackman will go and join Lollichon and Wycombe’s own goalkeeper coach, Barry Richardson, for a review of his recent efforts. “We go through videos of the game and work on things I could do better.”

Ainsworth, one of the Football League’s brightest young managers, believes that Blackman, whose Chelsea contract runs until 2019, will play Premier League football one day. The player himself refuses to give up on his dream of doing it at Stamford Bridge. “I’d like to go on loan again – maybe League One or higher –and get as much experience and show I can be a number one at Chelsea, and then go in and contest the number one position.

Blackman in action for Chelsea U21s (Getty)

“It is different from when you are playing reserves and you might hear ‘He’s doing well, maybe he will train with first team’,” he adds. “Now it’s like, ‘OK, he’s a football player’. Against Cambridge I made a couple of saves and we got our first proper away win, and that’s a great feeling. With the penalties as well people are saying ‘Look, Jamal is saving penalties’. It’s getting my name out and saying ‘I can play football, I am here and [Thibaut] Courtois watch out’.”

He laughs as he says this, but a big performance at White Hart Lane would add weight to his words. And he would certainly not be daunted if he really did end up having to face a penalty from Harry Kane, once a colleague in England’s junior sides – or any other Tottenham forward, for that matter.