Egan said: "You're playing against top teams every week, so you're being asked different questions and coming up against the best strikers. It can only benefit me and make me a better player.

"I'm just looking to keep improving and keep doing what I'm doing every week over there and keep doing well."

Egan's career has taken him from his release by Sunderland, where he suffered a serious injury during a loan spell at Bradford, back to the top flight via Gillingham and Brentford.

He was part of the Blades side which secured an unlikely promotion from the Sky Bet Championship at the end of last season and which has made light of the step up to the big time despite the added rigours that has brought.

Egan said: "I suppose the Championship is really physically demanding, playing every Saturday and Tuesday. I think the Premier League is more mentally demanding.

"You come up against players – you give them one chance, they're going to take it. Especially in my position, you're going to have to be focused for every second of the game, because as soon as you allow a player of that calibre in on goal, it's going to be a goal.

"Personally I feel like my performances have been good. I've really enjoyed the step up. I'm trying to embrace it and really have a good few games and good season now and show that I belong."

If Egan does get a chance against the Bulgarians, he could find himself lining up alongside a debutant in the shape of Luton striker James Collins.

The 28-year-old former Aston Villa trainee is another man who has had to work his way back up the ladder after an early setback, and currently finds himself playing Championship football and scoring goals after back-to-back promotions with the Hatters.

With David McGoldrick, who scored the Republic's late equaliser against Switzerland on Thursday evening, and Callum Robinson having been released because of injury, he and Scott Hogan are the only specialist frontmen in the squad, a fact which brings Shane Long's omission into ever sharper focus.

Collins said: "Me and John were talking the other day – it was not so long ago when we were playing against each other in League One for Gillingham and Shrewsbury.

" So to see how far we've both come since then – obviously, John playing in the Premier League now and myself in the Championship – it can show any young player that, if you do have a setback, you can only bounce back if you work hard."

Collins scored against Egan's Gillingham in a 2-2 draw that day in November 2015, and the defender was left in little doubt as to his ability.

Egan said: "He's a handful, he's a good finisher, to be fair. James has been brilliant and anywhere he's been, he's scored goals.

"When you're going through the scores on Saturday, any team he's played for, he's always been on the scoresheet, which is your job as a striker."