The Sheffield United product has enjoyed a remarkable 15 months, in which he has gone from being on the periphery of the Blades' League One squad to becoming a Premier League regular with Everton.
And the prospect of another landmark moment for Calvert-Lewin, who has already fired England's Under-20s to World Cup glory and won his first caps for the Three Lions' Under-21s this year, has got some Sheffield United fans seeing pound signs.
Does a full international call up trigger any other payments to United @JamesShield1— Batts (@SBatts79) 10 November 2017
But are the Blades actually in line for a windfall if the 20-year-old makes his senior debut next week? According to a Sheffield Star report from September 2016, they should have already received the full £1.4 million owed by Everton.
It reads: "The Star understands that United can expect to receive a guaranteed £1 million from Everton over the course of the teenager’s contract... United will receive the remaining £400,000 if Calvert-Lewin wins an England under-21 cap or makes a senior appearance for Ronald Koeman’s side [both of which have now been ticked off]."
But even though Everton's debts appear to be settled for the time being, United are said to be due a percentage of any future Calvert-Lewin sale.
It is claimed the Sheffielder could be joined by Liverpool's Dominic Solanke and Leicester City's Demarai Gray in Gareth Southgate's updated squad.