In the UK, sales, streams and video views are tracked from 0:00 on a Friday to 23:59 the following Thursday, with the charts being announced on Friday afternoons.
At the half-way stage on Monday, the Baddiel & Skinner & The Lightning Seeds song was leading the race to Number One, but it seems to have become more of a close fight since then.
And with the Croatia match just hours away, will a fresh demand for the track help push the anthem over the line?
According to the Official Charts Company, as of today the song is 5,000 sales ahead of its nearest rival – which on Monday was George Ezra’s Shotgun.
Three Lions is currently at the top of the live-updating bestseller list on iTunes, which helped it top the unofficial Big Top 40 countdown last weekend; but it needs to also hold its momentum with streaming services if it’s going to maintain its lead until the end of the week.
Bear in mind here that in modern Official Charts terms, 100 streams on a paid-for subscription service are weighted to the equivalent of one sale; as are 600 streams or video views on a free streaming platform.
At time of writing, Three Lions is at No18 on Spotify’s most-streamed list in the United Kingdom – and could well skyrocket tonight during the semi-final clash against Croatia.
If England win, presumably the sales and streams will continue to come in big numbers until the end of the tournament.
But if England lose, perhaps the song will fall off a cliff overnight and George Ezra will have a clear path to overtake them by end-of-play Thursday night.
Ezra himself has called for fans to knock him off Number 1, saying in a Twitter video: “Thanks to you lovely people, Shotgun has been number one for two weeks running.
“That is amazing, but I think it’s time we knock it off the number one spot with Three Lions.
“We go out, we download and we stream Three Lions and we get it to number one.”
He added: “And you know why? It’s because it’s coming home.”
This week’s Official Charts will be announced on Friday.