Neymar, the most expensive player in football history, and Ralston were involved in a heated confrontation during PSG's 5-0 win at Parkhead on Tuesday night, the Celtic defender laughing in the Brazilian's face at one point.
The 18-year-old has reportedly been on the Toffees' radar since the end of last season, when the right-back was given a chance in the first team.
The Sun understands that scouts were at the Toulon tournament where he represented Scotland Under-20s, and then in Paisley where he played for the Under-21s against Holland last week.
Ralston refused to be intimidated by Neymar, and said it was just like facing "any other player".
So how do the two sides compare in the money stakes? Sportsmail takes a look
"It wasn't a big deal".
But it has now been revealed that Neymar, who was laughed at and shouted in the face of by Ralston during the game, kept the shirt so he could donate it to the charity of the wife of Celtic and Liverpool legend Kenny Dalglish. I won't dwell on that too much.
Ralston is contracted to Celtic until 2019 but it looks as if the Scottish champions will have a struggle to keep the teenager if he carries on his current rate of progress.
However, Everton may view Halston as an ideal candidate to eventually take over from Seamus Coleman and Cuco Martina at right-back.
ESPN Distances Itself From Anchor Who Called Trump 'Bigot'
New: A statement from the National Association of Black Journalists on the White House's call to fire Jemele Hill . Hill deleted Monday's incendiary tweets and hasn't posted anything since ESPN weighed in on Tuesday.
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