Everton's Ross Barkley
The pair faced off during Everton's visit to Tottenham on Sunday, which ended in a 3-2 win for Dembele's team.
Ahead of the game, Barkley named the Belgian the hardest player he's played against, telling the Toffees' Youtube channel: "I played against him when I was 18 or 19 and I thought it was very tough.
"He's probably the hardest player I've played against. He's a strong player, he gets his foot in well and dictates play."
And Roberts, who won two FA Cups and a UEFA Cup with Spurs, clearly agrees with Barkley's assessment, posting: "spot on about @mousadembele what a player he is and so strong 13 games left in league and looking is on "
If recent reports are anything to go by, Barkley and Dembele might well be teammates at Tottenham next season.
The 23-year-old is one of several young English players to be linked with a move to north London in recent months, along with Harry Maguire, Wilfried Zaha and Andre Gray.
The Everton academy product is out of contract at Goodison Park next summer and is yet to sign an extension, meaning he could be available at a knock-down price this summer.
Would Barkley be a good partner for Dembele in Tottenham's midfield?
Tottenham players Mousa Dembele and Harry Kane celebrate